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Westpac Banking Corp. – ‘424B5’ on 11/10/20

On:  Tuesday, 11/10/20, at 8:53pm ET   ·   As of:  11/12/20   ·   Accession #:  1047469-20-5461   ·   File #:  333-228294

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  As Of               Filer                 Filing    For·On·As Docs:Size             Issuer                      Filing Agent

11/12/20  Westpac Banking Corp.             424B5      11/10/20    1:878K                                   Merrill Corp./New/FA

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 1: 424B5       Prospectus - Primary Offering or Shelf Securities   HTML    648K 
                - New Facts or Events                                            

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PROSPECTUS
TABLE OF CONTENTS

Filed Pursuant to Rule 424(b)(5)
Registration No. 333-228294

CALCULATION OF REGISTRATION FEE

(1)

The registration fee of US$163,650 is calculated in accordance with Rule 457(r) of the US Securities Act of 1933, as amended.

(2)

Represents an indeterminate number of fully paid ordinary shares in the capital of the registrant, which we refer to as the Ordinary Shares, that may be issued from time to time upon conversion of the 2.668% Subordinated Notes due 2030, which we refer to as the notes.

(3)

Pursuant to Rule 457(i) under the Securities Act, no separate registration fee is required for the Ordinary Shares underlying the notes because no additional consideration is to be received in connection with the exercise of the conversion privilege.

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PROSPECTUS SUPPLEMENT
(TO PROSPECTUS DATED NOVEMBER 9, 2018)

US$1,500,000,000

Westpac Banking Corporation
(ABN 33 007 457 141)
2.668% Subordinated Notes due 2035

Subject, upon the occurrence of a Non-Viability Trigger Event, to Conversion or possible
Write-off, as more fully described in the accompanying prospectus

            We are offering US$1,500,000,000 aggregate principal amount of our 2.668% subordinated notes due November 15, 2035, which we refer to as the notes. From and including November 16, 2020, which we refer to as the Issue Date, to but excluding the interest payment date on November 15, 2030, which we refer to as the Reset Date, the notes will bear interest at a rate of 2.668% per year, and on and after the Reset Date to but excluding November 15, 2035, which we refer to as the Maturity Date, the notes will bear interest at a fixed rate per year equal to the 5-Year U.S. Treasury Rate plus the Spread (rounded to three decimal places with 0.0005 rounded upwards) (each as defined herein). Interest will accrue on the notes from and including the Issue Date. Interest will be payable semi-annually in arrears on May 15 and November 15 of each year, subject in each case to the applicable business day convention set forth in this prospectus supplement, and certain solvency conditions described herein, beginning on May 15, 2021. We may redeem all, but not less than all, of the notes at our option on the Reset Date as described herein and under "Description of the Subordinated Debt Securities—Redemption of Subordinated Debt Securities—General" in the accompanying prospectus. We may also redeem all, but not less than all, of the notes if specified events occur involving Australian taxation or regulation as described herein and under "Description of the Subordinated Debt Securities—Redemption of Subordinated Debt Securities—Redemption for Taxation Reasons" and "Description of the Subordinated Debt Securities—Redemption of Subordinated Debt Securities—Redemption for Regulatory Reasons" in the accompanying prospectus. Redemption is subject to the prior written approval of the Australian Prudential Regulation Authority, which we refer to as APRA (which may or may not be given).

            The notes will be our direct, unsecured and subordinated obligations as described under "Description of the Subordinated Debt Securities—Ranking", "Description of the Subordinated Debt Securities—Additional Provisions—Status and Subordination" and "Description of the Subordinated Debt Securities—Additional Provisions—Winding-Up" in the accompanying prospectus. The notes will constitute a separate series of Subordinated Debt Securities as described in the accompanying prospectus.

            The notes are complex financial instruments and are not a suitable or appropriate investment for all investors. In some jurisdictions, regulatory authorities have adopted or published laws, regulations or guidance that limit or prohibit the offer or sale of securities such as these securities to certain types of investors. By purchasing, or making or accepting an offer to purchase, these notes from us and/or the underwriters in the United States, each prospective investor represents, warrants, agrees with and undertakes to us and to each underwriter that it qualifies as a "qualified institutional buyer" as defined in Rule 144A of the Securities Act. See "Plan of Distribution" in the accompanying prospectus.

            The notes are subject, upon the occurrence of a Non-Viability Trigger Event, to Conversion or possible Write-off (each as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus), as more fully described under "Description of the Notes—Non-viability, Conversion and Write-off" in this prospectus supplement and "Description of the Subordinated Debt Securities" in the accompanying prospectus. If any notes are Converted following a Non-Viability Trigger Event, it is likely that the Maximum Conversion Number (as defined herein) will apply and limit the number of Ordinary Shares to be issued. In this case, the value of the Ordinary Shares received is likely to be significantly less than the Outstanding Principal Amount (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) of those notes. The Australian dollar may depreciate in value against the U.S. dollar by the time of Conversion. In that case, the Maximum Conversion Number is more likely to apply.

            If Conversion of the notes (or a percentage of the Outstanding Principal Amount of the notes) does not occur for any reason within five ASX Business Days after the Non-Viability Trigger Event Date (each as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus), the notes (or a percentage of the Outstanding Principal Amount of the notes to be Converted) will be Written-off and the holders' rights in relation to the notes (including with respect to payments of interest or accrued interest, and the repayment of Outstanding Principal Amount and, upon Conversion, the receipt of Ordinary Shares (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) issued in respect of such notes) will be immediately and irrevocably written-off and terminated with effect on and from the Non-Viability Trigger Event Date, as described under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus.

            Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

            Investing in the notes involves risks. To read about certain factors you should consider before investing in the notes, see "Forward-Looking Statements" on page S-v and "Risk Factors" beginning on page S-11 of this prospectus supplement, and the risk factors set forth in our Annual Report on Form 20-F for the financial year ended September 30, 2020 filed with the Securities and Exchange Commission, which we refer to as the 2020 Form 20-F, and which is incorporated by reference in this prospectus supplement and the accompanying prospectus.

            The notes will not be protected accounts or deposit liabilities of Westpac Banking Corporation for the purpose of the Banking Act 1959 of Australia, which we refer to as the Australian Banking Act, or the financial claims scheme established under the Australian Banking Act (an Australian Government scheme that protects depositors of banks like Westpac from potential loss due to their failure), which we refer to as the FCS, are not subject to the depositor protection provisions of the Australian Banking Act, and are not insured or guaranteed by (1) the Commonwealth of Australia or any governmental agency of Australia, (2) the United States Federal Deposit Insurance Corporation or any other governmental agency or instrumentality of the United States, (3) any compensation scheme of the Commonwealth of Australia or the United States, or (4) any other entity.

            The notes will not be listed on any securities exchange. Currently, there is no public market for the notes.

            The underwriters expect that the notes will be ready for delivery in book-entry form only through The Depository Trust Company and its participants, including Euroclear Bank SA/NV and Clearstream Banking S.A., on or about November 16, 2020.

Joint Book-Running Managers

Co-Managers

November 9, 2020

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TABLE OF CONTENTS

PROSPECTUS

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SPECIAL NOTICE TO INVESTORS REGARDING AUTOMATIC CONVERSION OR WRITE-OFF UPON THE OCCURRENCE OF A NON-VIABILITY TRIGGER EVENT

        The notes are subject, upon the occurrence of a Non-Viability Trigger Event, to Conversion or possible Write-off, as more fully described in the accompanying prospectus. If any notes are Converted following a Non-Viability Trigger Event, it is likely that the Maximum Conversion Number will apply and limit the number of Ordinary Shares to be issued. In this case, the value of the Ordinary Shares received is likely to be significantly less than the Outstanding Principal Amount of those notes. The Australian dollar may depreciate in value against the U.S. dollar by the time of Conversion. In that case, the Maximum Conversion Number is more likely to apply.

        If Conversion of the notes (or a percentage of the Outstanding Principal Amount of the notes) does not occur for any reason within five ASX Business Days after the Non-Viability Trigger Event Date, the notes (or a percentage of the Outstanding Principal Amount of the notes to be Converted) will be Written-off and the holders' rights in relation to the notes (including with respect to payments of interest or accrued interest, and the repayment of Outstanding Principal Amount and, upon Conversion, the receipt of Ordinary Shares issued in respect of such notes) will be immediately and irrevocably written-off and terminated with effect on and from the Non-Viability Trigger Event Date, as described under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus.

OTHER IMPORTANT NOTICES

        You should rely only on information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and any free writing prospectus with respect to the offering of the notes filed by us with the Securities and Exchange Commission, which we refer to as the SEC. We have not, and the underwriters have not, authorized anyone to provide you with different or additional information. If anyone provides you with different, additional or inconsistent information, you should not rely on it. You should assume that the information in this prospectus supplement, the accompanying prospectus and any free writing prospectus with respect to the offering of the notes filed by us with the SEC and the documents incorporated by reference herein and therein is only accurate as of the respective dates of such documents. Our business, financial condition, results of operations and prospects may have changed since those dates.

        We are offering to sell, and are seeking offers to buy, the notes only in jurisdictions where offers and sales of the notes are permitted. The distribution of this prospectus supplement and the accompanying prospectus and the offering of the notes in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement and the accompanying prospectus must inform themselves about and observe any restrictions relating to the offering of the notes and the distribution of this prospectus supplement and the accompanying prospectus outside the United States. This prospectus supplement and the accompanying prospectus do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any notes offered by this prospectus supplement and the accompanying prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

        None of this prospectus supplement, the accompanying prospectus or any related free writing prospectus is a prospectus for the purposes of the Prospectus Regulation (as defined below). This prospectus supplement, the accompanying prospectus and any related free writing prospectus have been prepared on the basis that any offer of notes in any Member State of the European Economic Area (the "EEA") or in the United Kingdom (each, a "Relevant State") will only be made to a legal entity which is a qualified investor under the Prospectus Regulation ("Qualified Investors"). Accordingly any person making or intending to make an offer in that Relevant State of notes which are the subject of the offering contemplated in this prospectus supplement, the accompanying prospectus and any related

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free writing prospectus may only do so with respect to Qualified Investors. Neither Westpac nor the underwriters have authorized, nor do they authorize, the making of any offer of notes other than to Qualified Investors in the EEA or in the United Kingdom. The expression "Prospectus Regulation" means Regulation (EU) 2017/1129.

        PROHIBITION OF SALES TO EEA AND UNITED KINGDOM RETAIL INVESTORS —The notes are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the EEA or the United Kingdom. For these purposes, a retail investor means a person who is one (or more) of: (i) a retail client as defined in point (11) of Article 4(1) of Directive 2014/65/EU, as amended ("MiFID II"); or (ii) a customer within the meaning of Directive (EU) 2016/97 ("IDD"), where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or (iii) not a qualified investor as defined in the Prospectus Regulation. Consequently no key information document required by Regulation (EU) No 1286/2014 (as amended, the "PRIIPs Regulation") for offering or selling the notes or otherwise making them available to retail investors in the EEA or in the United Kingdom has been prepared and therefore offering or selling the notes or otherwise making them available to any retail investor in the EEA or in the United Kingdom may be unlawful under the PRIIPs Regulation.

        The communication of this prospectus supplement, the accompanying prospectus, any related free writing prospectus and any other document or materials relating to the issue of the notes offered hereby is not being made, and such documents and/or materials have not been approved, by an authorized person for the purposes of section 21 of the United Kingdom's Financial Services and Markets Act 2000, as amended (the "FSMA"). Accordingly, such documents and/or materials are not being distributed to, and must not be passed on to, the general public in the United Kingdom. The communication of such documents and/or materials as a financial promotion is only being made to those persons in the United Kingdom who have professional experience in matters relating to investments and who fall within the definition of investment professionals (as defined in Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the "Financial Promotion Order")), or who fall within Article 49(2)(a) to (d) of the Financial Promotion Order, or who are any other persons to whom it may otherwise lawfully be made under the Financial Promotion Order (all such persons together being referred to as "relevant persons"). In the United Kingdom, the notes offered hereby are only available to, and any investment or investment activity to which this prospectus supplement, the accompanying prospectus and any related free writing prospectus relates will be engaged in only with, relevant persons. Any person in the United Kingdom that is not a relevant person should not act or rely on this prospectus supplement, the accompanying prospectus or any related free writing prospectus or any of their contents.

PRESENTATION OF INFORMATION

        This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of the offering of the notes and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference in this prospectus supplement and the accompanying prospectus. The second part is the accompanying prospectus which gives more general information about our Debt Securities, including our Subordinated Debt Securities, some of which may not apply to this offering.

        If the information in this prospectus supplement is inconsistent with information contained in the accompanying prospectus or any document incorporated by reference in this prospectus supplement or the accompanying prospectus on or prior to the date hereof, you should rely on the information contained in this prospectus supplement.

        Unless otherwise indicated, or the context otherwise requires, references in this prospectus supplement to the "Group", "we", "us" and "our" or similar terms are to Westpac Banking

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Corporation and its controlled entities (within the meaning of Section 50AA of the Corporations Act 2001 of Australia, which we refer to as the Australian Corporations Act), and references to "Westpac" are to Westpac Banking Corporation (ABN 33 007 457 141).

        We publish our consolidated financial statements in Australian dollars. In this prospectus supplement, unless otherwise stated or the context otherwise requires, references to "dollars", "$", or "A$" are to Australian dollars, references to "US$", "USD" or "U.S. dollars" are to United States dollars and references to "NZ$", "NZD" or "NZ dollars" are to New Zealand dollars.

        Certain amounts that appear in this prospectus supplement may not sum due to rounding.

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FORWARD-LOOKING STATEMENTS

        This prospectus supplement contains or incorporates by reference statements that constitute "forward-looking" statements within the meaning of Section 27A of the Securities Act of 1933, as amended, which we refer to as the Securities Act. Forward-looking statements are statements about matters that are not historical facts. Forward-looking statements appear in a number of places in this prospectus supplement and the accompanying prospectus and the information incorporated by reference herein and therein and include statements regarding our intent, belief or current expectations with respect to our business and operations, market conditions, results of operations and financial condition, including, without limitation, future loan loss provisions and financial support to certain borrowers. Words such as "will", "may", "expect", "intend", "seek", "would", "should", "could", "continue", "plan", "estimate", "anticipate", "believe", "probability", "risk", "aim" or other similar words are used to identify forward-looking statements. These forward-looking statements reflect our current views with respect to future events and are subject to change, certain risks, uncertainties and assumptions which are, in many instances, beyond our control, and have been made based upon management's expectations and beliefs concerning future developments and their potential effect upon us. There can be no assurance that future developments will be in accordance with our expectations or that the effect of future developments on us will be those anticipated. Actual results could differ materially from those expected, depending on the outcome of various factors, including, but not limited to, those set forth in our 2020 Form 20-F and the other documents incorporated by reference in this prospectus supplement or the accompanying prospectus. Those factors include, but are not limited to:

•

the effect of the global COVID-19 pandemic, which has had, and is expected to continue to have, a negative impact on our business and global economic conditions, adversely affected a wide range of Westpac's key suppliers, third-party contractors and customers, created increased volatility in financial markets and may result in increased impairments, defaults and write-offs;



•

the effect of, and changes in, laws, regulations, taxation or accounting standards or practices and government policy, particularly changes to liquidity, leverage and capital requirements;



•

regulatory investigations, reviews and other actions, inquiries, litigation, fines, penalties, restrictions or other regulator imposed conditions, including as a result of our actual or alleged failure to comply with laws (such as financial crime laws), regulations or regulatory policy;



•

the failure to comply with financial crime obligations, which has had, and could further have, adverse effects on our business and reputation;



•

internal and external events which may adversely impact our reputation;



•

litigation and other legal proceedings and regulator investigations and enforcement actions;



•

information security breaches, including cyberattacks;



•

reliability and security of our technology and risks associated with changes to technology systems;



•

the stability of Australian and international financial systems and disruptions to financial markets and any losses or business impacts we or our customers or counterparties may experience as a result;



•

market volatility, including uncertain conditions in funding, equity and asset markets;



•

an increase in defaults in credit exposures because of a deterioration in economic conditions;



•

adverse asset, credit or capital market conditions;



•

the incidence of inadequate capital levels under stressed conditions;

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•

the risk that governments will default on their debt obligations or will be unable to refinance their debts as they fall due;



•

changes to our credit ratings or the methodology used by credit rating agencies;



•

levels of inflation, interest rates (including low or negative interest rates), exchange rates and market and monetary fluctuations and volatility;



•

an increase in defaults, write-offs and provisions for credit impairments;



•

changes in economic conditions, consumer spending, saving and borrowing habits in Australia, New Zealand and other countries (including as a result of tariffs and protectionist trade measures) in which we or our customers or counterparties conduct our or their operations and our ability to maintain or to increase market share, margins and fees, and control expenses;



•

the effects of competition, including from established providers of financial services and from non-financial services entities, in the geographic and business areas in which we conduct our operations;



•

poor data quality or poor data retention;



•

the effectiveness of our risk management policies, including internal processes, systems and employees, and operational risks resulting from ineffective processes and controls, as well as breakdowns in processes and procedures requiring remediation activity;



•

the incidence or severity of Westpac-insured events;



•

the occurrence of environmental change (including as a result of climate change) or external events in countries in which we or our customers or counterparties conduct our or their operations;



•

changes to our critical accounting estimates and judgments and changes to the value of our intangible assets;



•

changes in political, social or economic conditions in any of the major markets in which we or our customers or counterparties operate;



•

the inability to syndicate or sell down underwritten securities, particularly during times of heightened market volatility;



•

the success of strategic decisions involving diversification or innovation, in addition to business expansion activity, business acquisitions and the integration of new businesses;



•

our ability to incur additional indebtedness and any limitations contained in the agreements governing such additional indebtedness; and



•

various other factors beyond our control.

        All forward-looking statements speak only as of the date made. We are under no obligation to update any forward-looking statements contained or incorporated by reference in this prospectus supplement, whether as a result of new information, future events or otherwise.

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S-1

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S-2

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RISK FACTORS

        Investors should carefully consider the risks described below and in the other information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus, including the risks described in the 2020 Form 20-F, before making an investment decision. The risks and uncertainties described below and in such other information are not the only ones facing us or you, as holders of the notes. Additional risks and uncertainties that we are unaware of, or that we currently deem immaterial, may become important factors that affect us or you, as holders of the notes.

The notes are loss absorption instruments that involve risk and may not be a suitable investment for all investors

        The notes are loss absorption instruments designed to comply with applicable Australian banking regulations and involve certain risks. Each potential investor of the notes must determine the suitability (either alone or with the help of a financial advisor) of an investment in the notes in light of its own circumstances. In particular, each potential investor should understand thoroughly the terms of the notes, such as the provisions governing the Conversion or Write-off, including under what circumstances a Non-Viability Trigger Event could occur.

        A potential investor should not invest in the notes unless it has the knowledge and expertise (either alone or with the help of a financial advisor) to evaluate how the notes will perform, subject to the risks set forth herein and the risks described in our 2020 Form 20-F, the resulting effects on the likelihood of the Conversion or Write-off and the value of the notes, and the resultant impact on the potential investor's overall investment portfolio. Prior to making an investment decision, potential investors should consider carefully, in light of their own financial circumstances and investment objectives, all the information contained in or incorporated by reference into this prospectus supplement and the accompanying prospectus.

Payments are subject to Westpac being Solvent and if it is not Solvent, no payment will be made in respect of the notes

        All of Westpac's obligations to make payments in respect of the notes are subject to Westpac being Solvent (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus). If Westpac is not Solvent at the time a payment would otherwise be due and payable or would not be Solvent immediately thereafter as a result of making such payment, no payment will be made in respect of the notes. Westpac's failure to pay in such circumstances will not be an event of default and any unpaid Outstanding Principal Amount will accrue interest and interest not paid will accumulate with compounding until it is paid and will be payable on the first business day on which Westpac is Solvent. However, if a Non-Viability Trigger Event occurs, all of Westpac's obligations to make payments in respect of the notes (to the extent Converted or Written-off) (including in respect of accrued but unpaid interest) will cease and holders of the notes will have no rights to recover any unpaid amounts and will receive Ordinary Shares upon Conversion, assuming Westpac is able to Convert the notes.

A Non-Viability Trigger Event may occur and the circumstances surrounding or triggering a Non-Viability Trigger Event are unpredictable

        If a Non-Viability Trigger Event occurs, Westpac must Convert or Write-off the notes.

        A "Non-Viability Trigger Event" occurs when APRA notifies Westpac in writing that it believes:

(a)

Conversion or Write-off of all or some notes, or conversion, write-off or write-down of all or some Relevant Securities (as defined under "Description of the Subordinated Debt Securities"

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in the accompanying prospectus) is necessary because, without it, Westpac would become non-viable; or

(b)

a public sector injection of capital, or equivalent support, is necessary because, without it, Westpac would become non-viable.

        APRA has not provided specific guidance as to how it will determine non-viability. Non-viability could be expected to include serious impairment of Westpac's financial position, concerns about our capital, funding or liquidity levels and/or insolvency. However, it is possible that APRA's definition of non-viability may not necessarily be confined to these matters and APRA's position on these matters may change over time. APRA has indicated that non-viability is likely to arise prior to insolvency. As the occurrence of a Non-Viability Trigger Event is at the discretion of APRA, there can be no assurance given as to the factors and circumstances that might give rise to such an event. A Non-Viability Trigger Event could occur at any time. It could occur on dates not previously contemplated by investors or which may be unfavorable in light of then-prevailing market conditions or investors' individual circumstances or timing preferences.

        The section entitled "Risks factors" in the 2020 Form 20-F sets out a number of general risks associated with Westpac's businesses. If one, or a combination, of these risks leads to a significant capital loss, or prolonged difficulties in raising funding or maintaining sufficient liquidity, Westpac believes this may be the type of situation in which APRA would become concerned and notify Westpac that it has become non-viable. These examples are not exhaustive and there may be other risks which affect the financial performance and condition of Westpac and, consequently, the likelihood of the occurrence of a Non-Viability Trigger Event.

The Ordinary Shares to be received upon Conversion are likely to be worth significantly less than the Outstanding Principal Amount of the notes

        Upon the occurrence of a Non-Viability Trigger Event, if the notes are required to be Converted, all or some notes (or a percentage of the Outstanding Principal Amount of each note) will Convert into the applicable Conversion Number of Ordinary Shares, subject to the Maximum Conversion Number. In these circumstances, it is likely that the Maximum Conversion Number will apply and limit the number of Ordinary Shares to be issued. Upon Conversion, the value of Ordinary Shares received is likely to be significantly less than the Outstanding Principal Amount of the notes because:

•

the VWAP during the five ASX Business Days on which trading in Ordinary Shares took place immediately preceding but not including the Non-Viability Trigger Event Date may differ from the Ordinary Share price on or after that date;



•

the number of Ordinary Shares holders receive for each note on Conversion is limited by the Maximum Conversion Number, which is based on 20% of the Issue Date VWAP. It is likely that the Maximum Conversion Number will apply if a Non-Viability Trigger Event has occurred and limit the number of Ordinary Shares to be issued; and



•

the Australian dollar may depreciate in value against the U.S. dollar by the Conversion Date. Any depreciation of the Australian dollar against the U.S. dollar by the Conversion Date will increase the likelihood of the Maximum Conversion Number applying on Conversion and will likely also reduce the U.S. dollar equivalent of Ordinary Shares received, particularly if such depreciation is significant. This is because:



•

the Maximum Conversion Number is based on an Issue Date VWAP in Australian dollars and the U.S. dollar Outstanding Principal Amount of each note converted to Australian dollars is based on the spot rate of exchange at the time of issue; and

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•

the Conversion Number is based on the VWAP in Australian dollars at the time of Conversion and the U.S. dollar Outstanding Principal Amount of each note converted to Australian dollars is based on the spot rate of exchange at the time of Conversion.

        The Maximum Conversion Number may be adjusted to reflect a consolidation, division or reclassification, or pro rata bonus issue, of Ordinary Shares. However, no adjustment will be made to it on account of other transactions which may affect the price of Ordinary Shares, including for example, rights issues, returns of capital, buy-backs or special dividends. The transactions that Westpac may undertake with respect to its share capital are not limited and any such action may increase the risk that holders receive only the Maximum Conversion Number and so adversely affect the position of holders.

        However, even though Conversion is the primary method of loss absorption, the notes are subject to possible Write-off.

Ordinary Shares are a different type of investment to the notes and investors may be obliged to accept Ordinary Shares

        While Westpac currently has Ordinary Shares listed on the ASX, the Ordinary Shares issued on Conversion may not be listed, for example, if Westpac is acquired by another entity and delisted. The Ordinary Shares may not be able to be sold at prices representing their value based on the VWAP. In particular, the VWAP price will be based on trading days which occurred immediately before the occurrence of the Non-Viability Trigger Event.

        Ordinary Shares are a different type of investment to the notes. Dividends are payable at the absolute discretion of Westpac and the amount of each dividend is also discretionary. In a Winding-Up, claims of holders of Ordinary Shares rank behind claims of holders of all other securities and debts of Westpac. The market price of Ordinary Shares may be more sensitive than that of the notes to changes in Westpac's performance, operational issues and other business issues.

        Potential investors in the notes should understand that if a Non-Viability Trigger Event occurs and the notes are Converted, investors are obliged to accept Ordinary Shares or have such Ordinary Shares issued to the Holders' Nominee to be delivered or sold on their behalf.

Westpac has no obligation to have or maintain Relevant Tier 1 Securities which are required to be Converted or Written-off ahead of the notes following a Non-Viability Trigger Event

        If Westpac is only required to Convert a certain amount of Relevant Securities (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) Westpac will determine the amount of notes which will be Converted or Written-off and other Relevant Securities which will be converted, written-off or written-down as follows:

•

first, Westpac will convert, write-off or write-down such number or amount of the face value or outstanding principal amount of all outstanding Relevant Tier 1 Securities (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) before Conversion or Write-off of the notes; and



•

second, if conversion, write-off or write-down of those Relevant Tier 1 Securities is not sufficient, Westpac will Convert or Write-off the notes and convert, write-off or write-down other Relevant Tier 2 Securities, as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus, on a pro-rata basis or in a manner that is otherwise, in the opinion of Westpac, fair and reasonable (subject to such adjustments as Westpac may determine to take into account the effect on marketable parcels and the need to round to whole numbers of Ordinary Shares and the authorized denominations

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of any Relevant Tier 2 Securities remaining on issue, and the need to effect the conversion immediately).

        However, Westpac has no obligation to have or maintain on issue Relevant Tier 1 Securities which are required to be converted, written-off or written-down ahead of the notes and other Relevant Tier 2 Securities and gives no assurance that there will be any such instruments on issue at the time at which the notes may be required to be Converted or Written-off.

Holders rights will be terminated if Conversion does not occur within five ASX Business Days after the Non-Viability Trigger Event Date

        If Conversion of the notes (or a percentage of the Outstanding Principal Amount of the notes) does not occur for any reason within five ASX Business Days after the Non-Viability Trigger Event Date (including, for example, due to applicable law, order of a court or action of any government authority, including regarding the insolvency, Winding-Up or other external administration of Westpac or as a result of Westpac's inability or failure to comply with its obligations under the terms and conditions of the notes in relation to Conversion), then the notes (or a percentage of the Outstanding Principal Amount of the notes to be Converted) will be Written-off and the rights of holders in relation to such notes (including with respect to payments of interest or accrued interest, and the repayment of Outstanding Principal Amount and, upon Conversion, the receipt of Ordinary Shares issued in respect of such notes) will be immediately and irrevocably written-off and terminated with effect on and from the Non-Viability Trigger Event Date and investors will lose all or some of their investment and will not receive any compensation.

In certain circumstances, an investor holding notes subject to Conversion may not receive Ordinary Shares, only the proceeds thereof, as the Ordinary Shares would be issued upon Conversion to the Holders' Nominee for immediate sale, which sale is likely to occur when market conditions are not favorable

        If an investor holding notes subject to Conversion: (i) notifies us no less than 15 business days prior to the Non-Viability Trigger Event Date that it does not wish to receive Ordinary Shares as a result of the Conversion (and does not subsequently notify us otherwise); (ii) is a Foreign Holder or an Ineligible Holder (each as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus); (iii) is a Clearing System Holder (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus); (iv) does not provide the information as set forth in Section 3.10 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus to us prior to the Non-Viability Trigger Event Date; or (v) where a FATCA Withholding (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) is required to be made in respect of the Ordinary Shares issued on the Conversion, the Ordinary Shares that the investor would receive on Conversion will instead be issued to the Holders' Nominee (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) (which may not be Westpac or any of its Related Entities (which has the meaning given by APRA from time to time)), which will sell the shares on behalf of that investor. The Holders' Nominee will have no duty to seek a fair market price, or to engage in an arm's length transaction in such sale, and market conditions are likely to have deteriorated following the Non-Viability Trigger Event that caused the Conversion.

        To enable Westpac to issue Ordinary Shares to an investor on Conversion, investors need to have appropriate securities accounts in Australia as set forth in Section 3.10 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus for the receipt of Ordinary Shares and to provide to us, prior to the Non-Viability Trigger Event Date, their name and address and certain security holder account and other details. Investors should understand that a failure

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to provide this information to us by the Non-Viability Trigger Event Date may result in Westpac issuing the Ordinary Shares to the Holders' Nominee which, if the information is not provided to the Holders' Nominee within 30 days of the date on which Ordinary Shares are issued to the Holders' Nominee, will sell the Ordinary Shares and pay the net proceeds to the investors. In this situation, investors will have no rights against us in relation to the Conversion and will not be able to trade in any Ordinary Shares issued to the Holders' Nominee.

Holders cannot request redemption or Conversion of the notes and may not be able to sell the notes at an acceptable price or at all

        Holders have no right to request redemption or Conversion of the notes at any time. Therefore, prior to the Maturity Date, unless Westpac has the right to and elects to redeem the notes early (redemption is subject to APRA's prior written approval, which may or may not be given) in order to realize an investment, a holder would need to sell its notes at the prevailing market price. Depending on market conditions at the time, the notes may be trading at a market price below the issue price and/or the market for the notes may not be liquid. Westpac does not guarantee that holders will be able to sell each note at an acceptable price or at all.

The Ordinary Share price used to calculate the Conversion Number of Ordinary Shares may be different from the market price of Ordinary Shares at the time of Conversion

        The number of Ordinary Shares issued to holders upon Conversion will generally depend on the VWAP of Ordinary Shares over the five ASX Business Days on which trading in Ordinary Shares took place immediately preceding but not including the Non-Viability Trigger Event Date, and is subject to the Maximum Conversion Number. Accordingly, the Ordinary Share price used to calculate the Conversion Number of Ordinary Shares may be different to the market price of Ordinary Shares at the time of Conversion so that the value of Ordinary Shares received may be less than the value of those Ordinary Shares based on the Ordinary Share price on the Non-Viability Trigger Event Date. See "—The Ordinary Shares to be received upon Conversion are likely to be worth significantly less than the Outstanding Principal Amount of the notes."

Because the subordinated indenture contains no limit on the amount of additional debt that we may incur, our ability to make timely payments on the notes you hold may be affected by the amount and terms of our future debt

        Our ability to make timely payments on our outstanding debt may depend on the amount and terms of our other obligations, including any additional Subordinated Debt Securities that we may issue. The subordinated indenture does not contain any limitation on the amount of indebtedness that we may issue in the future. As we issue additional Subordinated Debt Securities under the subordinated indenture or incur other indebtedness, unless our earnings grow in proportion to our debt and other fixed charges, our ability to service the notes on a timely basis may become impaired.

The terms of the subordinated indenture and the notes provide only limited protection against significant events that could adversely impact your investment in the notes

        The subordinated indenture governing the notes does not:

•

require us to maintain any financial ratios or specific levels of net worth, revenues, income, cash flow or liquidity;



•

restrict our subsidiaries' ability to issue securities or otherwise incur indebtedness or other obligations that would be senior to our equity interests in our subsidiaries and therefore rank effectively senior to the notes with respect to the assets of our subsidiaries;

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•

restrict our ability to repurchase or prepay any other of our securities or other indebtedness; or



•

restrict our ability to make investments or to repurchase, or pay dividends or make other payments in respect of, Ordinary Shares or other securities ranking junior to the notes.

        As a result of the foregoing, when evaluating the terms of the notes, you should be aware that the terms of the subordinated indenture and the notes do not restrict our ability to engage in, or to otherwise be a party to, a variety of corporate transactions, circumstances and events that could have an adverse impact on your investment in the notes.

We may fail to pay principal or interest and there are limited remedies available for an event of default

        There is a risk that we may default on payment of some or all of the principal or interest on the notes. If we do not pay some or all of the principal or interest on the notes, holders of notes may lose some or all of the money invested in the notes.

        The remedies available to holders of notes in the event of a default in the payment of principal or interest are limited. Failure to pay principal or interest on the notes because the solvency conditions described herein are not satisfied is not an event of default.

        If principal or interest on the notes is not paid in circumstances where the solvency conditions described herein have been satisfied, that is an event of default and the holder of notes may institute proceedings:

•

to recover principal or interest on the notes then due and payable but unpaid (subject to our being able to make the payment and remain Solvent);



•

to obtain an order for specific performance of any other obligation in respect of the notes; or



•

for a winding-up of us in Australia.

        There is a risk that the entire amount owed may not be recovered even if the holder of notes institutes proceedings against us. Further, although the subordinated indenture and the notes may specify certain remedies (for example, seeking an order for the winding-up of us in Australia), the grant of those remedies may be in the discretion of a court and, as such, may not be granted.

        Further, a holder of notes will have no right to accelerate payment or exercise any other remedies (including any right to sue for damages) as consequences of any default other than as specifically described in this prospectus supplement and the accompanying prospectus. In the event of a Winding-Up in Australia (but not in any other jurisdiction), the notes will become immediately due and payable, unless they have been Converted or Written-Off. This will be the only circumstance in which the payment of principal on notes may be accelerated.

We have broad rights to redeem the notes, including in the event of certain tax and regulatory events and, if we do so, that could adversely affect your return on the notes

        We may redeem all, but not less than all, of the notes at our option on the Reset Date. We may also redeem all, but not less than all, of the notes at any time following the occurrence of an Adverse Tax Event (as defined under "Description of the Subordinated Debt Securities—Redemption of Subordinated Debt Securities—Redemption for Taxation Reasons" in the accompanying prospectus) or Regulatory Event (as defined under "Description of the Subordinated Debt Securities—Redemption of Subordinated Debt Securities—Redemption for Regulatory Reasons" in the accompanying prospectus), provided that we have obtained, in the case of an Adverse Tax Event, a supporting opinion of legal or tax advisers of recognized standing in Australia (or, if a Relevant Transaction (as defined under "Description of the Subordinated Debt Securities—Redemption of Subordinated Debt Securities—Redemption for Taxation Reasons" in the accompanying prospectus) occurs and the home jurisdiction

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for tax purposes of such other entity is not Australia, legal or tax advisers of recognized standing in such other jurisdiction), or, in the case of a Regulatory Event, a supporting opinion of advisers of recognized standing in Australia or confirmation from APRA.

        An Adverse Tax Event will occur if we determine that as a result of any amendment to, clarification of or change in Tax Legislation (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) which has been or will be effected or any Administrative Action (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) under or in connection with Tax Legislation or any amendment to, clarification of, or change in, any such Administrative Action, being in each case by a legislative body, court, government authority or regulatory body on or after the relevant Issue Date (but which we did not expect at the Issue Date or, upon the occurrence of a Relevant Transaction and the home jurisdiction for tax purposes of such other entity is not Australia, the date the Relevant Transaction is completed):

•

there is a material risk that we would be exposed to a more than de minimis adverse tax consequence in relation to the notes;



•

we determine that any interest payable on the notes is not, or may not be, allowed as a deduction for the purposes of Australian income tax; or



•

we have or will become obliged to pay additional amounts.

        A Regulatory Event will occur if either:

•

as a result of any amendment to, clarification of or change (including any announcement of a change that will be introduced) in any law or regulation of the Commonwealth of Australia or the Prudential Standards (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) or any official administrative pronouncement or action or judicial decision interpreting or applying such law, regulation or Prudential Standards, which amendment, clarification or change is effective, or pronouncement, action or decision is announced, on or after the Issue Date of the notes; or



•

written confirmation is received from APRA after the Issue Date of the notes that,

we are not or will not be entitled to treat all of the notes as Tier 2 Capital (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) in whole, provided that, in each case, we did not expect at the Issue Date that the matter giving rise to the Regulatory Event would occur.

        If we elect to redeem notes, APRA's prior written approval is required. There can be no certainty that APRA will provide its prior written approval. We may only redeem the notes if we replace them with capital of the same or better quality (and the replacement is done under conditions that are sustainable for Westpac's income capacity) or obtain confirmation that APRA is satisfied that we do not have to replace the notes.

        Holders of notes have no right to request or require a redemption of the notes. Any redemption may occur on dates not previously contemplated by holders of notes, which may be disadvantageous in light of market conditions or holders' individual circumstances. This means that the period for which holders of notes will be entitled to the benefit of the rights attaching to the notes is unknown.

        Where holders of notes receive cash on redemption, the rate of return at which such holders could reinvest their funds may be lower than the interest rate on the notes. Further, upon redemption, holders of notes will receive the Outstanding Principal Amount of the notes which may be less than their market value immediately prior to redemption.

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The interest rate on the notes could be reduced and the market value of the notes could be adversely impacted when the interest rate is reset on the Reset Date

        When the interest rate is reset on the Reset Date, there is a risk that the new interest rate may become less attractive when compared to the rates of return available on comparable securities issued by us or other entities. The interest rate will be reset on the Reset Date based on the 5-Year U.S. Treasury Rate as published in the most recent H.15 (as defined herein), and such H.15 which includes a yield to maturity for U.S. Treasury securities with a maturity of five years may have been published some time prior to the Reset Determination Date, and, as a result, may be less than the interest rate that applies immediately prior to the Reset Date, which would affect the amount of any interest payments under the notes and may adversely affect the market value of the notes. See "Description of the Notes."

Any changes to the capital adequacy framework in Australia may adversely impact the price of the notes or increase the chance of Conversion of the notes

        Any fall in our Common Equity Tier 1 Capital Ratio (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) as a result of changes to APRA's capital adequacy framework may adversely impact the market price of the notes or potentially increase the chance at a later date that Conversion of the notes takes place due to the occurrence of a Non-Viability Trigger Event (a Non-Viability Trigger Event will occur where APRA notifies us in writing that it believes Conversion of some or all of the notes or a public sector injection of capital, or equivalent support, is necessary because, without it, we would become non-viable).

Westpac has substantial liabilities which would have a higher priority in the event of its insolvency

        The notes will be our direct, unsecured and subordinated obligations. In the event of a Winding-Up, to the extent the notes have not previously been Converted or Written-off, the notes would (i) be subordinate to, and rank junior in right of payment to, the obligations of Westpac to Senior Creditors (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus), and certain debts required to be preferred by law, and all such obligations to Senior Creditors and debts required to be preferred by law shall be entitled to be paid in full before any payment shall be paid on account of any sums payable in respect of the notes, (ii) rank equally with obligations of Westpac to the holders of other Subordinated Debt Securities that have not been Converted or Written-off (or that have been partially Converted or Written-off), and the obligations of Westpac to holders of Equal Ranking Instruments and (iii) rank prior to, and senior in right of payment to, the obligations of Westpac to holders of Ordinary Shares and other Junior Ranking Capital Instruments. Section 13A(3) of the Australian Banking Act provides that if Westpac becomes unable to meet its obligations or suspends payment, the assets of Westpac in Australia are to be made available to meet certain of Westpac's liabilities in priority to all other liabilities of Westpac (including the obligations of Westpac under the notes). However, it is unlikely a Winding-Up will occur without a Non-Viability Trigger Event having occurred first and the notes being Converted or Written-Off. In that event:

•

if the notes have Converted into Ordinary Shares, holders will rank equally with existing holders of Ordinary Shares; and



•

if the notes are Written-Off, all rights in relation to the notes will be terminated, and holders will not have their Outstanding Principal Amount repaid or receive any outstanding interest or accrued interest, or have the right to have the notes Converted into Ordinary Shares. In such an event, a holder's investment in the notes will lose all of its value and such holder will not receive any compensation.

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        The notes will not be protected accounts or deposit liabilities of Westpac for the purposes of the Australian Banking Act.

        The liabilities which have priority, by virtue of Section 13A(3) of the Australian Banking Act, to the claims of holders in respect of the notes will be substantial, as such liabilities include (but are not limited to) liabilities owed to APRA in respect of amounts payable by APRA to holders of protected accounts (as defined below) kept with Westpac in connection with the financial claims scheme established under the Australian Banking Act, which we refer to as the FCS, costs of APRA in exercising its powers and performing its functions relating to Westpac in connection with the FCS, liabilities in Australia in relation to protected accounts kept with Westpac, debts due to the Reserve Bank of Australia, which we refer to as the RBA, and liabilities under certified industry support contracts. Section 13A(3) applies in a winding-up of Westpac and other circumstances if Westpac is unable to meet its obligations or suspends payment. A "protected account" is either (a) an account where the "authorised deposit-taking institution" is required to pay the account-holder, on demand or at an agreed time, the net credit balance of the account, or (b) another account or financial product prescribed by regulation.

        Further, certain assets, such as the assets of Westpac in a cover pool for covered bonds issued by Westpac, are excluded from constituting assets in Australia for the purposes of Section 13A of the Australian Banking Act, and these assets are subject to the prior claims of the covered bond holders and certain other secured creditors in respect of the covered bonds. The assets which are subject to such prior claims may also be substantial. In addition, future changes to applicable law may extend the debts required to be preferred by law or the assets to be excluded.

        In addition, in Section 16(2) of the Australian Banking Act, certain other debts of Westpac due to APRA shall in a winding-up of Westpac have, subject to Section 13A(3) of the Australian Banking Act, priority over all other unsecured debts of Westpac, and Section 86 of the Reserve Bank Act 1959 of Australia provides that in a winding-up of Westpac, debts due by Westpac to the RBA shall, subject to Section 13A(3) of the Australian Banking Act, have priority over all other debts of Westpac.

        Therefore, in the event of Westpac's insolvency, there is no assurance that Westpac will have sufficient assets to repay the notes in full or at all. See "Description of the Subordinated Debt Securities—Ranking" in the accompanying prospectus.

Holders of the notes or the Ordinary Shares will not be entitled to receive any gross up or other additional amounts if any person is required to withhold or deduct amounts arising under or in connection with FATCA from any payments made with respect to the notes or the Ordinary Shares

        Legislation known as "FATCA" was enacted in the United States on March 18, 2010. This description is based on Sections 1471 to 1474 of the U.S. Internal Revenue Code of 1986, as amended, which we refer to as the Code, including any regulations or official interpretations issued, agreements (including, without limitation, intergovernmental agreements) entered into or non-U.S. laws enacted with respect thereto, which we refer to as FATCA. Future guidance may affect the application of FATCA to the notes and the Ordinary Shares.

        It is possible that, in order to comply with FATCA, we (or, if the notes or the Ordinary Shares are held through another financial institution, such other financial institution) may be required (pursuant to an agreement entered into with the United States or under applicable law (including pursuant to the terms of any applicable intergovernmental agreement entered into between the United States and any other jurisdiction)) (i) to request certain information from the holders or beneficial owners of the notes or the Ordinary Shares, which information may be provided to the U.S. Internal Revenue Service, which we refer to as the IRS, and (ii) in the case of such other financial institution to withhold U.S. tax on any portion of any payment with respect to the notes, with respect to the issuance of any Ordinary Shares upon any Conversion or with respect to the Ordinary Shares treated as a foreign passthru

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payment made two years or more after the date on which the final regulations that define "foreign passthru payments" are published if such information is not provided or if payments are made to certain foreign financial institutions that have not entered into a similar agreement with the United States (and are not otherwise required to comply with the FATCA regime under applicable law (including pursuant to the terms of any applicable intergovernmental agreement entered into between the United States and any other jurisdiction)).

        If any person is required to withhold or deduct amounts arising under or in connection with FATCA from any payments made with respect to the notes, with respect to the issuance of any Ordinary Shares upon any Conversion or with respect to the Ordinary Shares, the holders and beneficial owners of the notes, and the holders and beneficial owners of the Ordinary Shares issued upon any Conversion, will not be entitled to receive any gross up or other additional amounts on account of any such withholding or deduction. FATCA is complex and its application to the notes, any Conversion and the Ordinary Shares remains uncertain. Prospective investors are advised to consult their own tax advisors as to the application of FATCA to the notes, any Conversion and the Ordinary Shares.

The IRS could successfully assert that the notes should be treated as indebtedness for U.S. federal income tax purposes, which could have adverse U.S. federal income tax consequences to a beneficial owner of the notes

        As discussed in "Taxation" in the accompanying prospectus, there is no statutory, judicial or administrative authority that directly addresses the U.S. federal income tax treatment of securities similar to the notes. It is therefore unclear whether the notes should be treated as indebtedness or equity for U.S. federal income tax purposes. Nonetheless, although not free from doubt, based upon an analysis of the relevant facts and circumstances, under applicable law as of the date hereof, it is more likely than not that the notes will be treated as equity for U.S. federal income tax purposes. Notwithstanding the foregoing, there can be no assurance that the IRS could not successfully assert that the notes should be treated as indebtedness for U.S. federal income tax purposes, and there can be no assurance that any such tax treatment would not have adverse U.S. federal income tax consequences to a beneficial owner of the notes. Due to the lack of authority regarding the classification of the notes for U.S. federal income tax purposes, prospective investors should consult their own tax advisors regarding the appropriate classification of the notes. See "Taxation—United States Taxation" in the accompanying prospectus.

The exercise of administrative powers by APRA or other regulatory authorities that supervise Westpac may result in adverse consequences to the trustee and holders of notes

        The exercise of administrative powers by APRA or other regulatory authorities that supervise Westpac may result in adverse consequences to the trustee and holders of notes. In particular, under the Australian Banking Act, for the purpose of protecting depositors and maintaining the stability of the Australian financial system, APRA has administrative power, among other things, to issue a direction to us regarding the conduct of our business, including prohibiting making payments with respect to our and certain of our related entities' debt obligations (including the notes), and, if we become unable to meet our obligations or suspend payment (and in certain other limited circumstances), to appoint a "Banking Act statutory manager" to take control of our business (including the businesses of certain of our related entities).

        The Australian Banking Act was recently amended to enhance APRA's powers to facilitate resolution of the entities it regulates (and their subsidiaries). Additional powers which have been given to APRA and which impact Westpac include greater oversight, management and directions powers in relation to Group entities which were previously not regulated by APRA, increased statutory management powers over certain other entities within the Group and changes which are designed to give statutory recognition to the conversion or write-off of regulatory capital instruments.

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Insolvency and similar proceedings are likely to be governed by Australian Law

        In the event that Westpac becomes insolvent, insolvency proceedings are likely to be governed by Australian law. Australian insolvency laws are different from the insolvency laws of certain other jurisdictions, including the United States. In particular, the voluntary administration procedure under the Australian Corporations Act, which provides for the potential re-organization of an insolvent company, is different from Chapter 11 under the U.S. Bankruptcy Code and may differ from similar provisions under the insolvency laws of other non-Australian jurisdictions.

        In addition, to the extent that the holders of the notes are entitled to any recovery with respect to the notes in any bankruptcy or certain other events in bankruptcy, insolvency, dissolution or reorganization relating to Westpac, those holders might not be entitled in such proceedings to a recovery in U.S. dollars and might be entitled only to a recovery in Australian dollars.

There is no existing public market for the notes, a market may not develop and you may have to hold your notes to maturity

        The notes are a new issue of securities and there is no existing trading market for the notes. We have been advised by the underwriters that the underwriters intend to make a secondary market for the notes. However, they are not obligated to do so and may discontinue making a secondary market for the notes at any time without notice. If a trading market for any series of notes develops, no assurance can be given as to how liquid that trading market will be. If any of the notes are traded after their initial issuance, they may trade at a discount from their initial offering price, depending upon prevailing interest rates, the market for similar securities and other factors, including general economic conditions and our financial condition, performance and prospects.

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USE OF PROCEEDS

        We estimate that the net proceeds from the offering of the notes, after taking into account the underwriting discount and deducting estimated offering expenses payable by us, will be US$1,493,633,850. We intend to use the net proceeds for general corporate purposes.

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CAPITALIZATION

        We set forth below our cash and cash equivalents and our capitalization as of September 30, 2020 and as adjusted to give effect to the issuance of the notes and the issuance of the 2040 Notes. This information should be read in conjunction with our consolidated financial statements, including the notes thereto, and other financial information pertaining to us incorporated herein by reference.

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DESCRIPTION OF THE NOTES

        The following description is a summary of certain terms of the notes. This summary supplements the description of the notes in the accompanying prospectus and, to the extent it is inconsistent, replaces the description in the accompanying prospectus. The descriptions of certain terms of the notes and the subordinated indenture do not purport to be complete, and reference is hereby made to the Third Amended and Restated Subordinated Indenture, referred to below, as supplemented by a supplemental indenture relating to the notes, which we refer to as the Supplemental Indenture, which will be filed as an exhibit to a Report on Form 6-K, and the Trust Indenture Act of 1939, as amended. You may also request copies of the Third Amended and Restated Subordinated Indenture and the Supplemental Indenture from us at our address set forth under "Where You Can Find More Information." References to "we", "us" and "our" in this description of the notes refer only to Westpac Banking Corporation and not to any of its subsidiaries.

General

        We will issue the notes under the Third Amended and Restated Subordinated Indenture, dated as of November 9, 2018, between Westpac Banking Corporation and The Bank of New York Mellon, as trustee, which we refer to as the base indenture, as supplemented by the Supplemental Indenture, to be dated the date of issuance of the notes, between us and the trustee. We refer to the base indenture, as supplemented by the Supplemental Indenture, together as the subordinated indenture.

        We will initially issue US$1,500,000,000 aggregate principal amount of the notes. The notes will be issued in minimum denominations of US$2,000 and integral multiples of US$1,000 in excess thereof, which shall be a "Denomination" for purposes of the definition in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus. We may from time to time, without the consent of the existing holders, create and issue additional notes having the same terms and conditions as the notes being offered hereby in all respects, except for Issue Date, issue price and, if applicable, the first date from which interest accrues and the first payment of interest thereon. Additional notes issued in this manner will be consolidated with, and will form a single series with, the previously outstanding notes unless such additional notes will not be treated as fungible with the notes being offered hereby for U.S. federal income tax purposes. The notes offered hereby and any additional notes of the same series would rank equally and ratably.

        The notes will be our direct, unsecured and subordinated obligations, subject to certain solvency conditions described herein. In the event of a Winding-Up, to the extent the notes have not previously been Converted or Written-off (or that have been partially Converted or Written-off), the notes would (i) be subordinate to, and rank junior in right of payment to, the obligations of Westpac to Senior Creditors, and certain debts required to be preferred by law, and all such obligations to Senior Creditors and debts required to be preferred by law shall be entitled to be paid in full before any payment shall be paid on account of any sums payable in respect of the notes, (ii) rank equally with obligations of Westpac to the holders of other Subordinated Debt Securities that have not been Converted or Written-off (or that have been partially Converted or Written-off), and the obligations of Westpac to holders of Equal Ranking Instruments and (iii) rank prior to, and senior in right of payment to, the obligations of Westpac to holders of Ordinary Shares and other Junior Ranking Capital Instruments. Section 13A(3) of the Australian Banking Act provides that if Westpac becomes unable to meet its obligations or suspends payment, the assets of Westpac in Australia are to be made available to meet certain of Westpac's liabilities in priority to all other liabilities of Westpac (including the obligations of Westpac under the notes). However, it is unlikely a Winding-Up will occur without a Non-Viability Trigger Event having occurred first and the notes being Converted or Written-off. In that event:

•

if the notes have Converted into Ordinary Shares, holders will rank equally with existing holders of Ordinary Shares; and

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•

if the notes are Written-off, all rights in relation to the notes will be terminated, and holders will not have their Outstanding Principal Amount repaid or receive any outstanding interest or accrued interest, or have the right to have the notes Converted into Ordinary Shares. In such an event, a holder's investment in the notes will lose all of its value and such holder will not receive any compensation.

        The notes will not be protected accounts or deposit liabilities of Westpac for the purposes of the Australian Banking Act.

        Each of the notes will constitute a separate series of Subordinated Debt Securities as described in the accompanying prospectus. Except as described in this prospectus supplement, the terms generally applicable to notes, as described under "Description of the Subordinated Debt Securities" in the accompanying prospectus, will be applicable to each of the notes.

        The notes are not entitled to the benefit of any sinking fund.

        The notes will mature on November 15, 2035.

        From and including November 16, 2020, which we refer to as the Issue Date, to but excluding the interest payment date on November 15, 2030, which we refer to as the Reset Date, the notes will bear interest on the Outstanding Principal Amount at a rate of 2.668% per year, and on and after the Reset Date to but excluding November 15, 2035, which we refer to as the Maturity Date, the notes will bear interest on the Outstanding Principal Amount at a fixed rate per year equal to the 5-Year U.S. Treasury Rate plus the Spread (rounded to three decimal places with 0.0005 rounded upwards) (each as defined below). Interest will accrue on the notes from and including the Issue Date. We will pay interest on the notes semi-annually in arrears on May 15 and November 15 of each year, subject in each case to the business day convention set forth below, and certain solvency conditions described herein, beginning on May 15, 2021, until the notes shall have been paid in full. Interest on a note will be paid to the person in whose name that note was registered at the close of business on the April 30 and October 31, as the case may be, whether or not a business day, prior to the applicable interest payment date, except in the case of the interest payment date that is also the Maturity Date of the notes. The amount of interest on the notes payable for any period less than a full interest period shall be computed on the basis of a 360-day year consisting of twelve 30-day months and the actual days elapsed in a partial month in such period. Subject to the limitations set forth in Section 3.1(b) under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus, any payment of principal or interest required to be made on an interest payment date that is not a business day will be made on the next succeeding business day, and no interest will accrue on that payment for the period from and after the interest payment date to the date of payment on the next succeeding business day.

        For purposes of the notes, "business day" means each Monday, Tuesday, Wednesday, Thursday and Friday that is not a day on which banking institutions in Sydney, Australia, New York, New York, or London, United Kingdom are authorized or obligated by law or executive order to close.

        Payments described in Section 3.1(b) under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus shall not be subject to delays on account of any business day convention.

        "5-Year U.S. Treasury Rate" is calculated by the calculation agent as an interest rate expressed as a percentage determined to be the per annum rate equal to the yield to maturity for U.S. Treasury securities with a maturity of five years as published in the most recent H.15.

        "H.15" means the daily statistical release designated as such, or any successor publication, published by the Board of Governors of the United States Federal Reserve System that establishes yield on actively traded U.S. Treasury securities under the caption "Treasury constant maturities", or any successor site or publication that establishes yield on actively traded U.S. Treasury securities, and

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"most recent H.15" means the H.15 which includes a yield to maturity for U.S. Treasury securities with a maturity of five years published closest in time but prior to the Reset Determination Date.

        "Reset Business Day" means a day on which commercial banks and foreign exchange markets settle payments and are open for general business (including dealing in foreign exchange and foreign currency deposits) in Sydney, Australia, New York, New York and London, United Kingdom.

        "Reset Determination Date" means the second Reset Business Day immediately preceding the Reset Date.

        "Spread" means 1.750 per cent per year, being the difference between the re-offer yield on the date hereof and the Benchmark 10-Year Treasury Yield at the time of pricing on the date hereof.

Redemption

        Subject to certain limitations, we will have the right to redeem the notes in whole, but not in part, at our option on the Reset Date, as described in the accompanying prospectus under the heading "Description of the Subordinated Debt Securities—Redemption of Subordinated Debt Securities—General".

        In addition, subject to certain limitations, if an Adverse Tax Event, as described in the accompanying prospectus under "Description of the Subordinated Debt Securities—Redemption of Subordinated Debt Securities—Redemption for Taxation Reasons", or a Regulatory Event, as described in the accompanying prospectus under "Description of the Subordinated Debt Securities—Redemption of Subordinated Debt Securities—Redemption for Regulatory Reasons", occurs, we will have the right to redeem each of the notes in whole, but not in part.

        Redemption is subject to APRA's prior written approval (which may or may not be given).

        If we redeem the notes in these circumstances, the redemption price of each note redeemed will be equal to 100% of the Outstanding Principal Amount of such note. In addition, we will pay to the holders of the notes redeemed in these circumstances accrued but unpaid interest to, but excluding, the date of redemption.

Non-viability, Conversion and Write-off

        The notes are subject, upon the occurrence of a Non-Viability Trigger Event, to Conversion or possible Write-off, as more fully described in the accompanying prospectus. If any notes are Converted following a Non-Viability Trigger Event, it is likely that the Maximum Conversion Number will apply and limit the number of Ordinary Shares to be issued. In this case, the value of the Ordinary Shares received is likely to be significantly less than the Outstanding Principal Amount of those notes. The Australian dollar may depreciate in value against the U.S. dollar by the time of Conversion. In that case, the Maximum Conversion Number is more likely to apply.

        If Conversion of the notes (or a percentage of the Outstanding Principal Amount of the notes) does not occur for any reason (including, for example, due to applicable law, order of a court or action of any government authority, including regarding the insolvency, Winding-Up or other external administration of Westpac or as a result of Westpac's inability or failure to comply with its obligations under the terms and conditions of the notes in relation to Conversion) within five ASX Business Days after the Non-Viability Trigger Event Date (each as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus), the notes (or a percentage of the Outstanding Principal Amount of the notes to be Converted) will be Written-off and the holders' rights in relation to the notes (including with respect to payments of interest or accrued interest, and the repayment of Outstanding Principal Amount and, upon Conversion, the receipt of Ordinary Shares issued in respect of such notes) will be immediately and irrevocably written-off and

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terminated with effect on and from the Non-Viability Trigger Event Date, as described under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus.

Events of Default

        The subordinated indenture provides that, if an event of default in respect of the notes shall have occurred and be continuing, the sole remedies for either the trustee or the holder of any outstanding notes shall be the remedies described below.

        The subordinated indenture defines an event of default in respect of the notes as any of the following events or circumstances:

•

Westpac fails to pay (i) any Outstanding Principal Amount in respect of the notes on the Maturity Date or within seven days thereafter, or (ii) any amount of interest in respect of the notes on the due date for payment thereof or within fourteen days thereafter, unless, in each case, prior to the commencement of a Winding-Up (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus), the failure to make such payment is the result of Westpac not being Solvent (as defined in Section 4 under "Description of the Subordinated Debt Securities—Additional Provisions" in the accompanying prospectus) on the date such payment is due or Westpac would not be Solvent immediately thereafter as a result of making such payment; or



•

a Winding-Up in Australia.

        Upon the occurrence of an event of default for a failure to pay principal or interest as described above, the sole remedies for the trustee or the holder of any notes shall be to bring proceedings:

•

to recover any amount then due and payable but unpaid on such notes (subject to Westpac being able to make the payment and remain Solvent);



•

to obtain an order for specific performance of any other obligation in respect of such notes; or



•

for a winding-up of Westpac in Australia.

        In the event of a Winding-Up in Australia (but not in any other jurisdiction), the notes will, without any further action on the part of the trustee or any holder thereof, become immediately due and payable by Westpac, unless they have been Converted or Written-off, and the trustee or any such holder may, subject to the limitations described under "Description of the Subordinated Securities—Additional Provisions—Status and Subordination" in the accompanying prospectus, prove or claim for the Outstanding Principal Amount of each note it holds (together with all interest accrued but unpaid to the date of payment). However, it is unlikely a Winding-Up will occur without a Non-Viability Trigger Event having occurred first and the notes being Converted or Written-off. In that event:

•

if the notes have Converted into Ordinary Shares, holders will rank equally with existing holders of Ordinary Shares; and



•

if the notes are Written-off, all rights in relation to the notes will be terminated, and holders will not have their Outstanding Principal Amount repaid or receive any outstanding interest or accrued interest, or have the right to have the notes Converted into Ordinary Shares. In such an event, a holder's investment in the notes will lose all of its value and such holder will not receive any compensation.

        In the event of the occurrence of any event of default, no remedy against Westpac (including, without limitation, any right to sue for a sum of damages which has the same economic effect as an acceleration of Westpac's payment obligations) shall be available to the trustee or any holder of any notes for the recovery of amounts owing in respect of the notes or in respect of any breach by Westpac

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of any obligation, condition or provision binding on it under the terms of the notes other than as described in this prospectus supplement, the applicable term sheet or the accompanying prospectus.

        A holder of notes will have no right to accelerate payment or exercise any other remedies (including any right to sue for damages) as a consequence of any default other than as specifically described in this prospectus supplement and the accompanying prospectus. In the event of a Winding-Up in Australia (but not in any other jurisdiction), the notes will become immediately due and payable, unless they have been Converted or Written-off. This will be the only circumstance in which the payment of principal on notes may be accelerated.

        If any note becomes due and payable as a result of an event of default, Westpac shall repay such amount as is equal to the Outstanding Principal Amount (or such other amount specified in or determined in accordance with this prospectus supplement or the applicable term sheet) together with all accrued but unpaid interest, if any.

        Under the Australian Banking Act, for the purpose of protecting depositors and maintaining the stability of the Australian financial system, APRA has administrative power, among other things, to issue a direction to us regarding the conduct of our business, including prohibiting making payments with respect to our debt obligations (including the notes), and, if we become unable to meet our obligations or suspend payment (and in certain other limited circumstances), to appoint an "ADI statutory manager" to take control of our business.

Governing Law

        The subordinated indenture and the notes will be governed by, and construed in accordance with, the laws of the State of New York, without regard to conflict of law principles, except that the Non-Viability Trigger Event, Write-off, Conversion and subordination provisions will be governed by, and construed in accordance with, the laws of the State of New South Wales, Commonwealth of Australia.

Notes Issued as Global Notes

        The notes are expected to be issued in the form of global notes. See "Description of the Subordinated Debt Securities—Global Securities" in the accompanying prospectus.

Book-Entry System

        All interests in the notes will be subject to the operations and procedures of DTC, Euroclear Bank SA/NV, which we refer to as Euroclear, and Clearstream Banking, société anonyme, which we refer to as Clearstream. The descriptions of the operations and procedures of DTC, Euroclear and Clearstream set forth below are provided solely as a matter of convenience. These operations and procedures are solely within the control of the respective settlement systems and are subject to change by them from time to time. We obtained the information in this section and elsewhere in this prospectus supplement concerning DTC, Euroclear and Clearstream and their respective book-entry systems from sources that we believe are reliable, but we take no responsibility for the accuracy of any of this information.

        The Depository Trust Company, New York, NY, will act as securities depository for the notes. The notes will be issued as fully-registered securities registered in the name of Cede & Co. (DTC's partnership nominee) or such other name as may be requested by an authorized representative of DTC. One fully-registered note certificate will be issued for each issue of the notes, each in the aggregate principal amount of such issue, and will be deposited with DTC. If, however, the aggregate principal amount of any issue exceeds $500 million, one certificate will be issued with respect to each

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$500 million of principal amount and an additional certificate will be issued with respect to any remaining principal amount of such issue.

        DTC, the world's largest securities depository, is a limited-purpose trust company organized under the New York Banking Law, a "banking organization" within the meaning of the New York Banking Law, a member of the Federal Reserve System, a "clearing corporation" within the meaning of the New York Uniform Commercial Code, and a "clearing agency" registered pursuant to the provisions of Section 17A of the Securities Exchange Act of 1934, as amended, which we refer to as the Exchange Act. DTC holds and provides asset servicing for over 3.5 million issues of U.S. and non-U.S. equity issues, corporate and municipal debt issues, and money market instruments from over 100 countries that DTC's participants, which we refer to as Direct Participants, deposit with DTC. DTC also facilitates the post-trade settlement among Direct Participants of sales and other securities transactions in deposited securities through electronic computerized book-entry transfers and pledges between Direct Participants' accounts. This eliminates the need for physical movement of securities certificates. Direct Participants include both U.S. and non-U.S. securities brokers and dealers, banks, trust companies, clearing corporations, and certain other organizations. DTC is a wholly-owned subsidiary of The Depository Trust & Clearing Corporation, which we refer to as DTCC. DTCC is the holding company for DTC, National Securities Clearing Corporation and Fixed Income Clearing Corporation, all of which are registered clearing agencies. DTCC is owned by the users of its regulated subsidiaries. Access to the DTC system is also available to others such as both U.S. and non-U.S. securities brokers and dealers, banks, trust companies, and clearing corporations that clear through or maintain a custodial relationship with a Direct Participant, either directly or indirectly, which we refer to as Indirect Participants. The DTC Rules applicable to its Direct Participants are on file with the Securities and Exchange Commission. More information about DTC can be found at www.dtcc.com and www.dtc.org.

        Purchases of notes under the DTC system must be made by or through Direct Participants, which will receive a credit for the notes on DTC's records. The ownership interest of each actual purchaser of each note, which we refer to as a Beneficial Owner, is in turn to be recorded on the Direct and Indirect Participants' records. Beneficial Owners will not receive written confirmation from DTC of their purchase. Beneficial Owners are, however, expected to receive written confirmations providing details of the transaction, as well as periodic statements of their holdings, from the Direct or Indirect Participant through which the Beneficial Owner entered into the transaction. Transfers of ownership interests in the notes are to be accomplished by entries made on the books of Direct and Indirect Participants acting on behalf of Beneficial Owners. Beneficial Owners will not receive certificates representing their ownership interests in notes, except in the event that use of the book-entry system for the notes is discontinued.

        To facilitate subsequent transfers, all notes deposited by Direct Participants with DTC are registered in the name of DTC's partnership nominee, Cede & Co., or such other name as may be requested by an authorized representative of DTC. The deposit of notes with DTC and their registration in the name of Cede & Co. or such other DTC nominee do not effect any change in beneficial ownership. DTC has no knowledge of the actual Beneficial Owners of the notes; DTC's records reflect only the identity of the Direct Participants to whose accounts the notes are credited, which may or may not be the Beneficial Owners. The Direct and Indirect Participants will remain responsible for keeping account of their holdings on behalf of their customers.

        Conveyance of notices and other communications by DTC to Direct Participants, by Direct Participants to Indirect Participants, and by Direct Participants and Indirect Participants to Beneficial Owners will be governed by arrangements among them, subject to any statutory or regulatory requirements as may be in effect from time to time.

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        Redemption notices shall be sent to DTC. If less than all of the notes within an issue are being redeemed, DTC's practice is to determine by lot the amount of the interest of each Direct Participant in such issue to be redeemed.

        Neither DTC nor Cede & Co. (nor any other DTC nominee) will consent or vote with respect to the notes unless authorized by a Direct Participant in accordance with DTC's money market instrument (MMI) procedures. Under its usual procedures, DTC mails an omnibus proxy to us as soon as possible after the record date. The omnibus proxy assigns Cede & Co.'s consenting or voting rights to those Direct Participants to whose accounts the notes are credited on the record date (identified in a listing attached to the omnibus proxy).

        Redemption proceeds, distributions, and interest payments on the notes will be made to Cede & Co., or such other nominee as may be requested by an authorized representative of DTC. DTC's practice is to credit Direct Participants' accounts upon DTC's receipt of funds and corresponding detail information from us or our agent on the payable date in accordance with their respective holdings shown on DTC's records. Payments by Participants to Beneficial Owners will be governed by standing instructions and customary practices, as is the case with securities held for the accounts of customers in bearer form or registered in "street name", and will be the responsibility of such Participant and not of DTC, our agent or us, subject to any statutory or regulatory requirements as may be in effect from time to time. Payment of redemption proceeds, distributions, and interest payments to Cede & Co. (or such other nominee as may be requested by an authorized representative of DTC) is the responsibility of Westpac or our agent, disbursement of such payments to Direct Participants will be the responsibility of DTC, and disbursement of such payments to the Beneficial Owners will be the responsibility of Direct and Indirect Participants.

        DTC may discontinue providing its services as depository with respect to the notes at any time by giving reasonable notice to us or our agent. Under such circumstances, in the event that a successor depository is not obtained, note certificates are required to be printed and delivered.

        We may decide to discontinue use of the system of book-entry-only transfers through DTC (or a successor securities depository). In that event, note certificates will be printed and delivered to DTC.

        Euroclear.    Euroclear was created in 1968 to hold securities for participants of Euroclear, which we refer to as Euroclear Participants, and to clear and settle transactions between Euroclear Participants through simultaneous electronic book-entry delivery against payment, thereby eliminating the need for physical movement of certificates and any risk from lack of simultaneous transfers of securities and cash. Euroclear includes various other services, including securities lending and borrowing and interfaces with domestic markets in several markets in several countries. Euroclear is operated by Euroclear Bank SA/NV, which we refer to as the Euroclear Operator, under contract with Euroclear Clearance Systems S.C., a Belgian cooperative corporation, which we refer to as the Cooperative. All operations are conducted by the Euroclear Operator, and all Euroclear securities clearance accounts and Euroclear cash accounts are accounts with the Euroclear Operator, not the Cooperative. The Cooperative establishes policy for Euroclear on behalf of Euroclear Participants. Euroclear Participants include banks (including central banks), securities brokers and dealers and other professional financial intermediaries and may include the underwriters. Indirect access to Euroclear is also available to other firms that clear through or maintain a custodial relationship with a Euroclear Participant, either directly or indirectly.

        The Euroclear Operator is regulated and examined by the Belgian Banking Commission. Distributions of principal and interest with respect to notes held through Euroclear will be credited to the cash accounts of Euroclear participants in accordance with the relevant system's rules and procedures, to the extent received by such system's depositary.

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        Clearstream.    Clearstream is incorporated under the laws of Luxembourg as a professional depositary. Clearstream holds securities for its participating organizations, which we refer to as Clearstream Participants, and facilitates the clearance and settlement of securities transactions between Clearstream Participants through electronic book-entry changes in accounts of Clearstream Participants, thereby eliminating the need for physical movement of certificates. Clearstream provides Clearstream Participants with, among other things, services for safekeeping, administration, clearance and establishment of internationally traded securities and securities lending and borrowing. Clearstream interfaces with domestic markets in several countries. As a professional depositary, Clearstream is subject to regulation by the Luxembourg Monetary Institute. Clearstream Participants are recognized financial institutions around the world, including underwriters, securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations, and may include the underwriters. Indirect access to Clearstream is also available to others, such as banks, brokers, dealers and trust companies that clear through or maintain a custodial relationship with a Clearstream Participant either directly or indirectly.

        Distributions with respect to notes held beneficially through Clearstream will be credited to cash accounts of Clearstream Participants in accordance with its rules and procedures to the extent received by the U.S. depositary for Clearstream.

        Links have been established among DTC, Clearstream and Euroclear to facilitate the initial issuance of the notes and cross-market transfers of the notes associated with secondary market trading. DTC will be linked indirectly to Clearstream and Euroclear through the DTC accounts of their respective U.S. depositaries.

        Global Clearance and Settlement Procedures.    Initial settlement for the notes will be made in immediately available funds. Transfers between participants in DTC will be effected in accordance with DTC's procedures, and will be settled in same-day funds. Transfers between participants in Euroclear or Clearstream will be effected in the ordinary way in accordance with their respective rules and operating procedures.

        Cross-market transfers between participants in DTC, on the one hand, and Euroclear or Clearstream participants, on the other hand, will be effected through DTC in accordance with DTC's rules on behalf of Euroclear or Clearstream, as the case may be, by its respective depositary. However, those cross-market transactions will require delivery of instructions to Euroclear or Clearstream, as the case may be, by the counterparty in that system in accordance with the rules and procedures and within the established deadlines (Brussels time) of that system. Euroclear or Clearstream, as the case may be, will, if the transaction meets its settlement requirements, deliver instructions to its respective depositary to take action to effect final settlement on its behalf by delivering or receiving interests in the relevant notes in DTC, and making or receiving payment in accordance with normal procedures for same-day funds settlement applicable to DTC. Euroclear Participants and Clearstream Participants may not deliver instructions directly to the depositaries for Euroclear or Clearstream.

        Because of time zone differences, the securities account of a Euroclear or Clearstream participant purchasing an interest in a note from a participant in DTC will be credited, and any such crediting will be reported to the relevant Euroclear or Clearstream participant, during the securities settlement processing day (which must be a business day for Euroclear and Clearstream) immediately following the settlement date of DTC. DTC has advised us that cash received in Euroclear or Clearstream as a result of sales of interests in a note by or through a Euroclear or Clearstream participant to a participant in DTC will be received with value on the settlement date of DTC but will be available in the relevant Euroclear or Clearstream cash account only as of the business day for Euroclear or Clearstream following DTC's settlement date.

        Although we understand that DTC, Euroclear and Clearstream have agreed to the foregoing procedures to facilitate transfers of interests in the notes among participants in DTC, Euroclear and

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Clearstream, they are under no obligation to perform or to continue to perform those procedures, and those procedures may be discontinued at any time. Neither we nor the trustee will have any responsibility for the performance by DTC, Euroclear or Clearstream or their respective participants or indirect participants of their respective obligations under the rules and procedures governing their operations.

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TAXATION

        For a general discussion of the material U.S. federal income tax and Australian tax considerations relating to the purchase, ownership, and disposition of the notes by certain holders, please refer to "Taxation" in the accompanying prospectus.

        The following summary replaces the section "Taxation—United States Taxation—FATCA Withholding" in the accompanying prospectus:

"FATCA Withholding

        It is possible that, in order to comply with FATCA, we (or, if the Subordinated Debt Securities or the Ordinary Shares are held through another financial institution, such other financial institution) may be required (pursuant to an agreement entered into with the United States or under applicable law (including pursuant to the terms of any applicable intergovernmental agreement entered into between the United States and any other jurisdiction)) (i) to request certain information from holders or beneficial owners of the Subordinated Debt Securities or the Ordinary Shares, which information may be provided to the IRS, and (ii) to withhold U.S. tax on any portion of any payment with respect to the Subordinated Debt Securities, with respect to the issuance of any Ordinary Shares upon any Conversion or with respect to the Ordinary Shares treated as a foreign passthru payment made two years or more after the date on which the final regulations that define "foreign passthru payments" are published if such information is not provided or if payments are made to certain foreign financial institutions that have not entered into a similar agreement with the United States (and are not otherwise required to comply with the FATCA regime under applicable law (including pursuant to the terms of any applicable intergovernmental agreement entered into between the United States and any other jurisdiction)).

        If we or any other person are required to withhold or deduct amounts arising under or in connection with FATCA from any payments made with respect to the Subordinated Debt Securities, with respect to the issuance of any Ordinary Shares upon any Conversion or with respect to the Ordinary Shares, holders and beneficial owners of the Subordinated Debt Securities, and the holders and beneficial owners of the Ordinary Shares issued upon any Conversion, will not be entitled to receive any gross up or other additional amounts on account of any such withholding or deduction. FATCA is complex and its application to the Subordinated Debt Securities, any Conversion and the Ordinary Shares remains uncertain. Each holder and beneficial owner should consult its own tax advisor regarding the application of FATCA to the Subordinated Debt Securities, any Conversion and the Ordinary Shares."

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UNDERWRITING (CONFLICTS OF INTEREST)

        BofA Securities, Inc., Citigroup Global Markets Inc., Goldman Sachs & Co, LLC, J.P. Morgan Securities LLC and Westpac Banking Corporation are acting as the representatives of the underwriters named below. Subject to the terms and conditions stated in the underwriting agreement dated the date of this prospectus supplement, each underwriter named below has agreed to severally purchase, and we have agreed to sell to that underwriter, the principal amount of notes set forth opposite the underwriter's name.

        The underwriting agreement provides that the obligations of the underwriters to purchase the notes offered hereby are subject to approval of legal matters by counsel and to other conditions. The underwriters are obligated to purchase all the notes if they purchase any of the notes.

        Westpac Banking Corporation, as underwriter, may reduce or eliminate its obligation to purchase the notes that it has agreed to purchase under the underwriting agreement. In that event, we shall have the right to require each underwriter other than Westpac Banking Corporation to purchase the principal amount of the notes that such underwriter agreed to purchase under the underwriting agreement, as shown in the table above, plus such underwriter's pro rata share (based on the principal amount of notes that such underwriter agreed to purchase under the underwriting agreement) of the notes that Westpac Banking Corporation, as underwriter, is no longer obligated to purchase.

        The underwriters have advised us that they propose to offer some of the notes directly to the public at the public offering price, set forth on the cover page of this prospectus supplement and some of the notes to dealers at the public offering price, less a concession not to exceed 0.250% of the principal amount of the notes. The underwriters may allow, and dealers may reallow, a concession not to exceed 0.150% of the principal amount of the notes. After the initial offering of the notes to the public, the representatives may change the public offering price and other selling terms. The offering of the notes by the underwriters is subject to receipt and acceptance and subject to the underwriters' right to reject any order in whole or in part. In connection with this offering of the notes, we will pay an underwriting discount to the underwriters of 0.400% (expressed as a percentage) of the principal amount of the notes.

        In connection with the offering of the notes, the representatives may engage in transactions that stabilize, maintain or otherwise affect the prices of the notes. Specifically, the underwriters may overallot in connection with the offering of the notes, creating a syndicate short position. In addition, the underwriters may bid for, and purchase, notes in the open market to cover syndicate short positions or to stabilize the prices of the notes. Finally, the underwriting syndicate may reclaim selling concessions allowed for distributing the notes in the offering of the notes, if the syndicate repurchases previously distributed notes in syndicate covering transactions, stabilization transactions or otherwise.

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Any of these activities may stabilize or maintain the market prices of the notes above independent market levels. The underwriters are not required to engage in any of these activities, and may end any of them at any time without notice.

        The underwriters also may impose a penalty bid. This occurs when a particular underwriter repays to the underwriters a portion of the underwriting discount received by it because the representatives have repurchased notes sold by or for the account of such underwriter in stabilizing or short covering transactions.

        We estimate that our total expenses, excluding the underwriting discount, for this offering will be US$366,150. The underwriters have agreed to reimburse us for certain of our expenses relating to this offering.

        We have agreed to indemnify the several underwriters against certain liabilities, including liabilities under the Securities Act, or to contribute to payments the underwriters may be required to make because of any of those liabilities.

        The notes are a new issue of securities with no established trading market. The notes will not be listed on any securities exchange or on any automated dealer quotation system. The underwriters may make a market in the notes after completion of the offering, but will not be obligated to do so and may discontinue any market-making activities at any time without notice. No assurance can be given as to the liquidity of the trading market for the notes or that an active public market for the notes will develop. If an active public market for the notes does not develop, the market price and liquidity of the notes may be adversely affected.

        Since trades in the secondary market generally settle in two business days, purchasers who wish to trade notes on the date of pricing or the next succeeding business day will be required, by virtue of the fact that the notes initially settle in T+4, to specify alternative settlement arrangements to prevent a failed settlement.

        ICBC Standard Bank Plc is restricted in its U.S. securities dealings under the United States Bank Holding Company Act and may not underwrite, subscribe, agree to purchase or procure purchasers to purchase notes that are offered or sold in the United States. Accordingly, ICBC Standard Bank Plc shall not be obligated to, and shall not, underwrite, subscribe, agree to purchase or procure purchasers to purchase notes that may be offered or sold by other underwriters in the United States. ICBC Standard Bank Plc shall offer and sell the notes constituting part of its allotment solely outside the United States.

Conflicts of Interest

        The underwriters and their respective affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. The underwriters and their affiliates have, directly and indirectly, provided various investment and commercial banking services to us and our affiliates for which they received customary fees and commissions. The underwriters and their affiliates may, from time to time, engage in other transactions with and perform services for us in the ordinary course of their business. In the ordinary course of their various business activities, the underwriters and their respective affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers, and such investment and securities activities may involve securities and/or instruments of Westpac. If any of the underwriters or their affiliates has a lending relationship with us, certain of those underwriters and affiliates routinely hedge and certain other of those underwriters or affiliates may hedge their credit exposure to us consistent with their customary risk management

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policies. Typically, these underwriters and their affiliates would hedge such exposure by entering into transactions which consist of either the purchase of credit default swaps or the creation of short positions in our securities, including potentially the notes offered hereby. Any such credit default swaps or short positions could adversely affect future trading prices of the notes offered hereby. The underwriters and their respective affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

        Westpac Banking Corporation is not a U.S. registered broker-dealer and, therefore, to the extent that it intends to effect any sales of the notes in the United States, it will do so through Westpac Capital Markets LLC, a U.S. registered broker dealer, which we refer to as WCM. WCM is an affiliate of Westpac Banking Corporation. This offering will be conducted in compliance with Rule 5121 of the Financial Industry Regulatory Authority, Inc., which we refer to as FINRA, regarding a FINRA member firm's distribution of the securities of an affiliate and related conflicts of interest. In accordance with FINRA Rule 5121, WCM may not make sales in this offering to any discretionary accounts without the prior written approval of the customer.

        This prospectus supplement, together with the accompanying prospectus and any prospectus describing the terms of the specific series of securities being offered and sold, may be used by Westpac or its U.S. broker-dealer subsidiary, Westpac Capital Markets LLC, which we refer to as WCM in connection with offers and sales of such securities in market-making transactions at negotiated prices related to prevailing market prices at the time of sale, or at other prices. Westpac or WCM may act as principal or agent in these transactions. Neither Westpac nor WCM is obligated to make a market in any of the securities referenced on the cover of this prospectus supplement and either Westpac or WCM may discontinue any market-making at any time without notice, at its sole discretion.

Offering Restrictions

Australia

        Neither this prospectus supplement nor the accompanying prospectus or any disclosure document (as defined in the Australian Corporations Act) in relation to the notes has been, or will be, lodged with the Australian Securities and Investments Commission, which we refer to as ASIC. Each underwriter has represented and agreed that, in connection with the distribution of the notes, it:

          (i)  has not offered for issue or sale, nor invited applications for the issue, sale or purchase of, any notes in Australia (including an offer or invitation which is received by a person in Australia);

         (ii)  will not offer for issue or sale, nor invite applications for the issue or sale of, or to purchase, any notes in Australia (including an offer or invitation which is received by a person in Australia); and

        (iii)  has not distributed or published, and will not distribute or publish, this prospectus supplement or any other offering material or advertisement relating to the notes in Australia;

        unless:

         (x)  (A) the aggregate amount payable on acceptance of the offer by each offeree or invitee for the notes of either series is a minimum amount (disregarding amounts, if any, lent by Westpac or another person offering the notes of such series or an associate (as defined in Division 2 of Part 1.2 of the Australian Corporations Act) of either of them) of A$500,000 (or its equivalent in an alternate currency); or (B) the offer or invitation is otherwise an offer or invitation for which no disclosure is required to be made under Parts 6D.2 or 7.9 of the Australian Corporations Act;

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         (y)  the offer, invitation or distribution complies with all applicable Australian laws and regulations in relation to the offer, invitation or distribution; and

         (z)  such action does not require any document to be lodged with the ASIC or the Australian Securities Exchange operated by ASX Limited.

Prohibition of Sales to EEA and United Kingdom Retail Investors

        Each underwriter has represented and agreed that it has not offered, sold or otherwise made available and will not offer, sell or otherwise make available any notes to any retail investor in the EEA and United Kingdom.

        For the purposes of this provision:

         (a)  the expression "retail investor" means a person who is one (or more) of the following:

          (i)  a retail client as defined in point (11) of Article 4(1) of MiFID II; or

         (ii)  a customer within the meaning of the IDD, where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or

        (iii)  not a qualified investor as defined in the Prospectus Regulation; and

         (b)  the expression "offer" includes the communication in any form and by any means of sufficient information on the terms of the offer and the notes to be offered so as to enable an investor to decide to purchase or subscribe for the notes.

France

        Each underwriter has represented and agreed that:

          (i)  in connection with its initial distribution of the notes, (A) it has not offered or sold and will not offer or sell, directly or indirectly, any notes to the public in the Republic of France and (B) offers and sales of notes will made in the Republic of France only to qualified investors as defined and in accordance with Articles L.411-1 and L.411-2 of the French Code monétaire et financier relating to qualified investors; and

         (ii)  it has not distributed or caused to be distributed and will not distribute or cause to be distributed in the Republic of France this prospectus supplement or any other offering material relating to the notes other than to investors to whom offers and sales of notes in the Republic of France may be made as described in (i)(B) above.

        In compliance with Article 211-4 of the General regulation of the Autorité des marchés financiers (French stock exchange authority) investors are informed that the notes have not been subject to a prospectus submitted for approval to the Autorité des marchés financiers.

        The persons or entities referred to in Article L.411-2.II.4 of the French Code monétaire et financier may purchase notes solely for their own account under the conditions referred to in Articles D.411-1, D.411-2, D.734-1, D.744-1 and D.754-1 and D.764-1 of the French Code monétaire et financier.

        The notes thus acquired cannot be distributed directly or indirectly to the public otherwise than in accordance with the conditions referred to in Articles L.411-1, L.412-1 and L.621-8 to L.621-8-3 of the French Code monétaire et financier.

The Netherlands

        Each underwriter has represented and agreed in respect of the notes that it has not offered and that it will not offer, directly or indirectly, any notes in The Netherlands and that such an offer may

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not be announced (whether electronically or otherwise), unless the notes are offered exclusively to persons who qualify as professional market parties within the meaning of article 1:1 of the Financial Markets Supervision Act (Wet op het financieel toezicht).

Hong Kong

        Each underwriter has represented and agreed that it has not offered or sold and will not sell or offer to sell in Hong Kong, by means of any document, any note other than: (i) to "professional investors" as defined in the Securities and Futures Ordinance (Cap. 571) of Hong Kong (the "SFO") and any rules made thereunder, or (ii) in other circumstances which do not result in the document being a "prospectus" as defined in the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32) of Hong Kong (the "C(WUMP)O") or which do not constitute an offer to the public within the meaning of the C(WUMP)O; and that it has not issued or had in its possession for the purposes of issue, and will not issue or have in its possession for the purpose of issue, where in Hong Kong or elsewhere, any advertisement, invitation or document relating to the notes, which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to notes which are or are intended to be disposed of only to persons outside Hong Kong or only to "professional investors" as defined in the SFO and any rules made thereunder.

Japan

        Each underwriter has represented and agreed that the notes have not been and will not be registered under the Financial Instruments and Exchange Law of Japan (Law No. 25 of 1948, as amended) (the "Financial Instruments and Exchange Law"), and has represented and agreed that it has not offered or sold and will not offer or sell the notes, directly or indirectly, in Japan or to, or for the account or benefit of, any Japanese Person or to, or for the account or benefit of, others for re-offering or resale, directly or indirectly, in Japan or to, or for the account or benefit of, any Japanese Person, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the Financial Instruments and Exchange Law and any other applicable laws, regulations and ministerial guidelines of Japan. For the purpose of this paragraph "Japanese Person" means any person resident in Japan, including any corporation or other entity organized under the laws of Japan.

Singapore

        This prospectus supplement has not been and will not be registered as a prospectus under the Securities and Futures Act, Chapter 289 of Singapore, which we refer to as the SFA, by the Monetary Authority of Singapore, and the offer of the notes in Singapore is made primarily pursuant to the exemptions under Sections 274 and 275 of the SFA. Accordingly, this prospectus supplement and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the notes may not be circulated or distributed, nor may the notes be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to any person in Singapore other than (a) to an institutional investor as defined in Section 4A of the SFA, which we refer to as an Institutional Investor, pursuant to Section 274 of the SFA, (b) to an accredited investor as defined in Section 4A of the SFA, which we refer to as an Accredited Investor, or other relevant person as defined in Section 275(2) of the SFA, which we refer to as a Relevant Person, and pursuant to Section 275(1) of the SFA, or to any person pursuant to an offer referred to in Section 275(1A) of the SFA, and in accordance with the conditions specified in Section 275 of the SFA and (where applicable) Regulation 3 of the Securities and Futures (Classes of Investors) Regulation 2018, or (c) otherwise pursuant to, and in accordance with, the conditions of any other applicable exemption or provision of the SFA.

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        It is a condition of the offer that where the notes are subscribed for or acquired pursuant to an offer made in reliance on Section 275 of the SFA by a Relevant Person which is:

          (i)  a corporation (which is not an Accredited Investor), the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an Accredited Investor; or

         (ii)  a trust (where the trustee is not an Accredited Investor), the purpose of which is to hold investments and each beneficiary of the trust is an individual who is an Accredited Investor,

securities or securities-based derivatives contracts (each as defined in Section 2(1) of the SFA) of that corporation or the beneficiaries' rights and interest (howsoever described) in that trust shall not be transferred within six months after that corporation or that trust has subscribed or acquired the notes except:

         (x)  to an Institutional Investor, an Accredited Investor, a Relevant Person, or which arises from an offer referred to in Section 275(1A) of the SFA (in the case of that corporation) or Section 276(4)(i)(B) of the SFA (in the case of that trust);

         (y)  where no consideration is or will be given for the transfer;

         (z)  where the transfer is by operation of law;

       (aa)  as specified in Section 276(7) of the SFA; or

       (bb)  as specified in Regulation 37A of the Securities and Futures (Offers of Investments) (Securities and Securities-based Derivatives Contracts) Regulations 2018.

        Notification under Section 309B(1) of the SFA—Unless otherwise stated in this prospectus supplement in respect of the notes, all notes shall be prescribed capital markets products (as defined in the Securities and Futures (Capital Markets Products) Regulations 2018) and Excluded Investment Products (as defined in MAS Notice SFA 04-M12: Notice on the Sale of Investment Products and MAS Notice FAA-N16: Notice on Recommendations on Investment Products).

United Kingdom

        Each underwriter has represented and agreed that:

          (i)  it has only communicated or caused to be communicated and will only communicate or cause to be communicated an invitation or inducement to engage in investment activity (within the meaning of Section 21 of the FSMA)) received by it in connection with the issue or sale of the notes in circumstances in which Section 21(1) of the FSMA would not, if Westpac was not an authorized person, apply to Westpac; and

         (ii)  it has complied and will comply with all applicable provisions of the FSMA with respect to anything done by it in relation to the notes in, from or otherwise involving the United Kingdom.

Canada

        The notes may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the notes must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

        Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus supplement and the accompanying prospectus

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(including any amendment hereto and thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser's province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser's province or territory for particulars of these rights or consult with a legal advisor.

        Pursuant to section 3A.3 of National Instrument 33-105 Underwriting Conflicts ("NI 33-105"), the underwriters are not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

Italy

        The offering of the notes has not been registered with the Commissione Nazionale per le Societ`a e la Borsa ("CONSOB") pursuant to Italian securities legislation and, accordingly, each underwriter has represented and agreed that, save as set out below, it has not offered or sold, and will not offer or sell, any notes in the Republic of Italy in an offer to the public and that sales of the notes in the Republic of Italy shall be effected in accordance with all Italian securities, tax and exchange control and other applicable laws and regulation.

        Accordingly, each of the underwriters has represented and agreed that it will not offer, sell or deliver any notes or distribute copies of this Prospectus Supplement and any other document relating to the notes in the Republic of Italy except:

        (1)   to "qualified investors", as referred to in Article 100 of Legislative Decree No. 58 of 24 February 1998, as amended (the "Decree No. 58") and defined in Article 34-ter, paragraph 1, let. b) of CONSOB Regulation No. 11971 of 14 May 1999, as amended ("Regulation No. 11971"); or

        (2)   in any other circumstances where an express exemption from compliance with the offer restrictions applies, as provided under Decree No. 58 or Regulation No. 11971.

        Any such offer, sale or delivery of the notes or distribution of copies of this prospectus supplement or any other document relating to the notes in the Republic of Italy must be:

        (a)   made by investment firms, banks or financial intermediaries permitted to conduct such activities in the Republic of Italy in accordance with Legislative Decree No. 385 of 1 September 1993 as amended, Decree No. 58, CONSOB Regulation No. 20307 of 15 February 2018, as amended and any other applicable laws and regulations;

        (b)   in compliance with Article 129 of Legislative Decree No. 385 of 1 September 1993, as amended, pursuant to which the Bank of Italy may request information on the issue or the offer of securities in the Republic of Italy and the relevant implementing guidelines of the Bank of Italy issued on 25 August 2015 (as amended on 10 August 2016); and

        (c)   in compliance with any other applicable notification requirement or limitation which may be imposed by CONSOB or the Bank of Italy.

Provisions relating to the secondary market in the Republic of Italy

        Investors should also note that, in any subsequent distribution of the notes in the Republic of Italy, Article 100-bis of Decree No. 58 may require compliance with the law relating to public offers of securities. Furthermore, where the notes are placed solely with "qualified investors" and are then systematically resold on the secondary market at any time in the 12 months following such placing, purchasers of notes who are acting outside of the course of their business or profession may in certain circumstances be entitled to declare such purchase void and, in addition, to claim damages from any

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authorised person at whose premises the notes were purchased, unless an exemption provided for under Decree No. 58 applies.

Switzerland

        The notes may not be publicly offered, directly or indirectly, in Switzerland within the meaning of the Swiss Financial Services Act (the "FinSA") and will not be admitted to trading on any trading venue (exchange or multilateral trading facility) in Switzerland. Neither this prospectus supplement nor any other offering or marketing material relating to the notes constitutes a prospectus as such term is understood pursuant to the FinSA, and neither this prospectus supplement nor any other offering or marketing material relating to the notes may be publicly distributed or otherwise made publicly available in Switzerland.

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WHERE YOU CAN FIND MORE INFORMATION

        We file annual and other reports and other information with the SEC under the Exchange Act. The SEC maintains an Internet site, http://www.sec.gov, which contains reports, proxy and information statements and other information regarding issuers that are subject to the SEC's reporting requirements.

        You may request a copy of any filings (excluding exhibits) referred to above and in "Incorporation of Information We File with the SEC" at no cost by contacting us at the following address: Westpac Banking Corporation, New York Branch, 575 Fifth Avenue, 39th Floor, New York, New York 10017-2422, Attention: Branch Manager. Telephone requests may be directed to such person at (212) 389-1269. Our website is available at www.westpac.com.au. Information contained in or accessible through the websites mentioned in this prospectus supplement does not form part of this prospectus supplement or the accompanying prospectus and all references in this prospectus supplement to websites are inactive textual references and are for information only.

        This prospectus supplement is a supplement to the accompanying prospectus contained in a registration statement that we have filed with the SEC relating to the notes to be offered. This prospectus supplement does not contain all of the information we have included in the registration statement, including the accompanying prospectus, and the accompanying exhibits and schedules in accordance with the rules and regulations of the SEC, and we refer you to the omitted information. The statements this prospectus supplement makes pertaining to the content of any contract, agreement or other document that is an exhibit to the registration statement necessarily are summaries of their material provisions and do not describe all exceptions and qualifications contained in those contracts, agreements or documents. You should read those contracts, agreements or documents for information that may be important to you. The registration statement, exhibits and schedules are available through the SEC's Internet site.

INCORPORATION OF INFORMATION WE FILE WITH THE SEC

        The SEC allows us to incorporate by reference the information we file with them, which means:

•

incorporated documents are considered part of this prospectus supplement;



•

we can disclose important information to you by referring you to those documents; and



•

information that we file with the SEC will automatically update and supersede this prospectus supplement and any previously incorporated information.

        We incorporate by reference the documents listed below which were filed with the SEC under the Exchange Act:

•

our annual report on Form 20-F for the financial year ended September 30, 2020; and



•

the information contained in Exhibit 1 (Pillar 3 Report) to our report on Form 6-K dated November 2, 2020.

        We also incorporate by reference each of the following documents that we will file with the SEC after the date of this prospectus supplement until this offering is completed:

•

reports filed under Sections 13(a) and (c) of the Exchange Act, including reports on Form 6-K if and to the extent specified in such report as being incorporated by reference in the accompanying prospectus; and



•

any reports filed under Section 15(d) of the Exchange Act.

        You should assume that the information appearing in this prospectus supplement is accurate only as of the date of this prospectus supplement and that information appearing in documents incorporated

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by reference herein is accurate only as of the respective dates of those documents. Our business, financial condition and results of operations may have changed since that date.

CURRENCY OF PRESENTATION AND EXCHANGE RATES

        We publish our consolidated financial statements in Australian dollars.

        The following table sets forth, for Westpac's financial years indicated, the high, low, average and period-end noon buying rates in New York City for cable transfers in Australian dollars as certified for customs purposes by the Federal Reserve Bank of New York, expressed in U.S. dollars per A$1.00. Westpac's financial year ends on September 30 of each year.

        Regulations in Australia restrict or prohibit payments, transactions and dealings with assets having a proscribed connection with certain countries or named individuals or entities subject to international sanctions or associated with terrorism.

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VALIDITY OF SECURITIES

        King & Wood Mallesons, our Australian counsel, will provide an opinion to the effect that we have duly authorized the issuance of the notes and will pass upon the validity of the Ordinary Shares. Additionally, the validity of the notes under New York law will be passed upon for us by our New York counsel, Debevoise & Plimpton LLP, New York, New York. The validity of the notes under New York law will be passed upon for the Underwriters by their United States counsel, Sidley Austin LLP, New York, New York.

EXPERTS

        The financial statements and management's assessment of the effectiveness of internal control over financial reporting (which is included in Management's Report on Internal Control Over Financial Reporting), incorporated in this prospectus supplement and the accompanying prospectus by reference to the Annual Report on Form 20-F for the financial year ended September 30, 2020, have been so incorporated in reliance on the report of PricewaterhouseCoopers, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting. PricewaterhouseCoopers is a member of the Chartered Accountants Australia and New Zealand.

LIMITATION ON INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM'S LIABILITY

        The liability of PricewaterhouseCoopers (an Australian partnership which we refer to as PwC Australia), with respect to claims arising out of its audit report described under "Experts" above, is subject to the limitations set forth in the Professional Standards Act 1994 of New South Wales, Australia, as amended, which we refer to as the Professional Standards Act, and Chartered Accountants Australia and New Zealand (NSW) scheme adopted by Chartered Accountants Australia and New Zealand and approved by the New South Wales Professional Standards Council pursuant to the Professional Standards Act, which we refer to as the NSW Accountants Scheme. For matters occurring on or prior to October 8, 2019, the liability of PwC Australia may be subject to the limitations set forth in predecessor schemes. The current NSW Accountants Scheme expires on October 7, 2024 unless further extended or replaced.

        The Professional Standards Act and the NSW Accountants Scheme may limit the liability of PwC Australia for damages with respect to certain civil claims arising in, or governed by the laws of, New South Wales directly or vicariously from anything done or omitted to be done in the performance of its professional services for us, including, without limitation, its audits of our financial statements. The extent of the limitation depends on the timing of the relevant matter and is:

•

in relation to matters occurring on or after October 8, 2013, a maximum liability for audit work of A$75 million; or



•

in relation to matters occurring on or prior to October 7, 2013, to the lesser of (in the case of audit services) ten times the reasonable charge for the service provided and a maximum liability for audit work of A$75 million.

        The limitations do not apply to claims for breach of trust, fraud or dishonesty. In addition, there is equivalent professional standards legislation in place in other states and territories in Australia and amendments have been made to a number of Australian federal statutes to limit liability under those statutes to the same extent as liability is limited under state and territory laws by professional standards legislation. Accordingly, liability for acts or omissions by PwC Australia in Australian states or territories other than New South Wales may be limited in a manner similar to that in New South Wales. These limitations of liability may limit recovery upon the enforcement in Australian courts of any judgment under US or other foreign laws rendered against PwC Australia based on or related to its audit report on our financial statements. Substantially all of PwC Australia's assets are located in Australia. However, the Professional Standards Act and the NSW Accountants Scheme have not been subject to extensive judicial consideration and therefore how the limitation might be applied by the courts and the effect of the limitation remain untested in a number of respects including its effect in respect of the enforcement of foreign judgments.

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EXPENSES

        The following table sets forth the aggregate expenses, other than the underwriting discount, to be paid by us in connection with this offering. All amounts shown are estimates, except for the SEC registration fee.