2Q23 Conference Call Slides

Greg Case

Chief Executive Officer

Christa Davies

Chief Financial Officer

Eric Andersen

President

Safe Harbor Statement

This communication contains certain statements related to future results, or states Aon's intentions, beliefs and expectations or predictions for the future, all of which are forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from either historical or anticipated results depending on a variety of factors. These forward-looking statements include information about possible or assumed future results of Aon's operations. All statements, other than statements of historical facts, that address activities, events or developments that Aon expects or anticipates may occur in the future, including such things as its outlook, future capital expenditures, growth in commissions and fees, changes to the composition or level of its revenues, cash flow and liquidity, expected tax rates, expected foreign currency translation impacts, business strategies, competitive strengths, goals, the benefits of new initiatives, growth of its business and operations, plans, and references to future successes, are forward- looking statements. Also, when Aon uses words such as "anticipate", "believe", "continue", "could", "estimate", "expect", "forecast", "intend", "looking forward", "may", "might", "plan", "potential" "probably", "project", "should", "will", "would" or similar expressions, it is making forward-looking statements.

The following factors, among others, could cause actual results to differ from those set forth in or anticipated by the forward looking statements: changes in the competitive environment, due to macroeconomic conditions (including impacts from instability in the banking or commercial real estate sectors) or otherwise, or damage to Aon's reputation; fluctuations in currency exchange, interest, or inflation rates that could impact our financial condition or results; changes in global equity and fixed income markets that could affect the retuon invested assets; changes in the funded status of Aon's various defined benefit pension plans and the impact of any increased pension funding resulting from those changes; the level of Aon's debt and the terms thereof reducing Aon's flexibility or increasing borrowing costs; rating agency actions that could limit Aon's access to capital and our competitive position; volatility in Aon's global tax rate due to being subject to a variety of different factors, including the adoption and implementation of OECD tax proposals; changes in Aon's accounting estimates or assumptions on Aon's financial statements; limits on Aon's subsidiaries' ability to pay dividends or otherwise make payments to Aon; the impact of legal proceedings and other contingencies, including those arising from acquisition or disposition transactions, errors and omissions and other claims against Aon; the impact of, and potential challenges in complying with, laws and regulations in the jurisdictions in which Aon operates, particularly given the global nature of Aon's operations and the possibility of differing or conflicting laws and regulations, or the application or interpretation thereof, across jurisdictions in which Aon does business; the impact of any regulatory investigations brought in Ireland, the U.K., the U.S. and other countries; failure to protect intellectual property rights or allegations that Aon infringes on the intellectual property rights of others; general economic and political conditions in different countries in which Aon does business around the world; the failure to retain, attract and develop experienced and qualified personnel; international risks associated with Aon's global operations, including impacts from military conflicts or political instability, such as the ongoing Russian war in Ukraine; the effects of natural or man-made disasters, including the effects of the COVID-19 and other health pandemics and the impacts of climate change; any system or network disruption or breach resulting in operational interruption or improper disclosure of confidential, personal, or proprietary data, and resulting liabilities or damage to our reputation; Aon's ability to develop, implement, update and enhance new systems; the actions taken by third parties that perform aspects of Aon's business operations and client services; the extent to which Aon is exposed to certain risks, including lawsuits, related to actions Aon may take in being responsible for making decisions on behalf of clients in Aon's investment businesses or in other advisory services that Aon currently provides, or may provide in the future; Aon's ability to continue, and the costs and risks associated with, growing, developing and integrating acquired business, and entering into new lines of business or products; Aon's ability to secure regulatory approval and complete transactions, and the costs and risks associated with the failure to consummate proposed transactions; changes in commercial property and casualty markets, commercial premium rates or methods of compensation; Aon's ability to develop and implement innovative growth strategies and initiatives intended to yield cost savings, and the ability to achieve such growth or cost savings; the effects of Irish law on Aon's operating flexibility and the enforcement of judgments against Aon; and adverse effects on the market price of Aon's securities and/or operating results.

Any or all of Aon's forward-looking statements may tuout to be inaccurate, and there are no guarantees about Aon's performance. The factors identified above are not exhaustive. Aon and its subsidiaries operate in a dynamic business environment in which new risks may emerge frequently. Accordingly, you should not place undue reliance on forward-looking statements, which speak only as of the dates on which they are made. In addition, results for prior periods are not necessarily indicative of results that may be expected for any future period. Further information concerning Aon and its businesses, including factors that potentially could materially affect Aon's financial results, is contained in Aon's filings with the SEC. See Aon's Annual Report on Form 10-K for the year ended December 31, 2022 for a further discussion of these and other risks and uncertainties applicable to Aon and its businesses. These factors may be revised or supplemented in subsequent reports filed with the SEC. Aon is not under, and expressly disclaims, any obligation to update or alter any forward-looking statement that it may make from time to time, whether as a result of new information, future events or otherwise.

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2023 U.S. GAAP Financials

Explanation of Non-GAAP Measures

This communication includes supplemental information not calculated in accordance with generally accepted accounting principles in the United States ("U.S. GAAP"), including organic revenue growth, free cash flow, free cash flow margin, retuon invested capital, adjusted operating income, adjusted operating margin, adjusted earnings per share, adjusted net income attributable to Aon shareholders, adjusted net income per share, and adjusted effective tax rate that exclude the effects of intangible asset amortization and impairment, pension settlements, capital expenditures, and certain other noteworthy items that affected results for the comparable periods. Organic revenue growth includes the impact of intercompany activity and excludes foreign exchange rate changes, acquisitions, divestitures, transfers between revenue lines, fiduciary investment income, and gains or losses on derivatives accounted for as hedges. Currency impact represents the effect on prior year period results if they were translated at current period foreign exchange rates. Reconciliations to the closest U.S. GAAP measure for each non-GAAP measure presented in this communication are provided in the attached appendices. Supplemental organic revenue growth information and additional measures that exclude the effects of certain items noted above do not affect net income or any other U.S. GAAP reported amounts. Free cash flow is cash flows from operating activity less capital expenditures. The adjusted effective tax rate excludes the applicable tax impact associated with expenses for estimated intangible asset amortization and impairment, and certain other noteworthy items. Management believes that these measures are important to make meaningful period-to-period comparisons and that this supplemental information is helpful to investors. Management also uses these measures to assess operating performance and performance for compensation. Non-GAAP measures should be viewed in addition to, not in lieu of, Aon's Consolidated Financial Statements. Industry peers provide similar supplemental information regarding their performance, although they may not make identical adjustments.

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Table of Contents

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