Non-GAAP Financial Measures Frontier uses certain non-GAAP financial measures in evaluating its
performance, including EBITDA, EBITDA margin, Adjusted EBITDA, Adjusted EBITDA margin, operating free cash flow, and adjusted operating expenses, each of which is described below. Management uses these non-GAAP financial measures internally to
(i) assist in analyzing Frontier's underlying financial performance from period to period, (ii) analyze and evaluate strategic and operational decisions, (iii) establish criteria for compensation decisions, and (iv) assist in the understanding
of Frontier's ability to generate cash flow and, as a result, to plan for future capital and operational decisions. Management believes that the presentation of these non-GAAP financial measures provides useful information to investors
regarding Frontier’s financial condition and results of operations because these measures, when used in conjunction with related GAAP financial measures (i) provide a more comprehensive view of Frontier’s core operations and ability to generate
cash flow, (ii) provide investors with the financial analytical framework upon which management bases financial, operational, compensation, and planning decisions and (iii) present measurements that investors and rating agencies have indicated
to management are useful to them in assessing Frontier and its results of operations. A reconciliation of these measures to the most comparable financial measures calculated and presented in accordance with GAAP is included in the accompanying
tables. These non-GAAP financial measures are not measures of financial performance or liquidity under GAAP, nor are they alternatives to GAAP measures and they may not be comparable to similarly titled measures of other companies. EBITDA is
defined as net income (loss) less income tax expense (benefit), interest expense, investment and other income (loss), pension settlement costs, gains/losses on extinguishment of debt, and depreciation and amortization. EBITDA margin is
calculated by dividing EBITDA by total revenue. Adjusted EBITDA is defined as EBITDA, as described above, adjusted to exclude, certain pension/OPEB expenses, restructuring costs and other charges, stock-based compensation expense, goodwill
impairment charges, and certain other non-recurring items. Adjusted EBITDA margin is calculated by dividing Adjusted EBITDA by total revenue. Management uses EBITDA, EBITDA margin, Adjusted EBITDA and Adjusted EBITDA margin to assist it in
comparing performance from period to period and as measures of operational performance. Management believes that these non-GAAP measures provide useful information for investors in evaluating Frontier’s operational performance from period to
period because they exclude depreciation and amortization expenses related to investments made in prior periods and are determined without regard to capital structure or investment activities. By excluding capital expenditures, debt repayments
and dividends, among other factors, these non-GAAP financial measures have certain shortcomings. Management compensates for these shortcomings by utilizing these non-GAAP financial measures in conjunction with the comparable GAAP financial
measures. Adjusted net income (loss) attributable to Frontier common shareholders is defined as net income (loss) attributable to Frontier common shareholders and excludes restructuring costs and other charges, pension settlement costs,
goodwill impairment charges, certain income tax items and the income tax effect of these items, and certain other non-recurring items. Adjusting for these items allows investors to better understand and analyze Frontier’s financial performance
over the periods presented. Management defines operating free cash flow, a non-GAAP measure, as net cash from operating activities less capital expenditures. Management uses operating free cash flow to assist it in comparing liquidity from
period to period and to obtain a more comprehensive view of Frontier’s core operations and ability to generate cash flow. Management believes that this non-GAAP measure is useful to investors in evaluating cash available to service debt. This
non-GAAP financial measure has certain shortcomings; it does not represent the residual cash flow available for discretionary expenditures, as items such as taxes, pension and OPEB costs, interest expense, and debt repayments are not deducted
in determining such measure. Management compensates for these shortcomings by utilizing this non-GAAP financial measure in conjunction with the comparable GAAP financial measure. Adjusted operating expenses is defined as operating expenses
adjusted to exclude depreciation and amortization, restructuring and other charges, goodwill impairment charges, certain pension/OPEB expenses, stock-based compensation expense, and certain other non-recurring items. Investors have indicated
that this non-GAAP measure is useful in evaluating Frontier’s performance. Projected GAAP financial measures are not provided herein because such figures are not available on a forward-looking basis and reconciliations of projected non-GAAP
financial measures are not provided because they could not be derived without unreasonable effort.The information in this presentation should be read in conjunction with the financial statements and footnotes contained in Frontier’s documents
filed with the U.S. Securities and Exchange Commission. 3