Aon announcement made under Irish regulatory requirements

Aon plc (NYSE: AON) (the “Company”) notes the recent media speculation regarding Willis Towers Watson.

The Company confirms that it is in the early stages of considering an all-share business combination with Willis Towers Watson. The Company emphasizes that, at this point, its evaluation of a potential transaction is at a preliminary stage and there can be no certainty that any transaction will take place nor as to the form or terms on which any transaction might be pursued.

A further announcement will be made in due course, as appropriate.

In accordance with Rule 2.4 of the Irish Takeover Rules, Aon reserves the right to vary the form and/or mix of consideration described in this announcement.

About Aon

Aon plc (NYSE:AON) is a leading global professional services firm providing a broad range of risk, retirement and health solutions. Our 50,000 colleagues in 120 countries empower results for clients by using proprietary data and analytics to deliver insights that reduce volatility and improve performance.

Forward-Looking Statements

This press release contains statements that are forward looking, as that term is defined by the Private Securities Litigation Reform Act of 1995. These forward-looking statements are based on management’s beliefs, as well as assumptions made by, and information currently available to, management. When used in this press release, the words “believe,” “anticipate,” “estimate,” “expect,” “intend,” “project,” “plans,” and similar expressions and the use of future dates are intended to identify forward looking statements. Although management believes that the expectations reflected in these forward-looking statements are reasonable, it can give no assurance that these expectations will prove to have been correct. These forward-looking statements involve risks and uncertainties that could cause actual results to differ materially from those predicted in any such forward-looking statements. Such factors include, but are not limited to, the possibility that a transaction will not be pursued and/or an offer will not be made, failure to obtain necessary shareholder or regulatory approvals or required financing or to satisfy any of the other conditions to a potential transaction, adverse effects on the market price of our Class A ordinary shares and on our operating results for any reason, including, without limitation, because of a failure to complete a transaction, failure to realize the expected benefits of a transaction, negative effects of an announcement or consummation or failure to consummate a transaction on the market price of our Class A ordinary shares, significant transaction costs and/or unknown liabilities and general economic and business conditions that affect the combined companies following any transaction. You are cautioned not to place undue reliance on any forward-looking statements, which speak only as of the date made. These statements are subject to certain risks, uncertainties, and assumptions.

Any or all of our forward-looking statements may turn out 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.

/Public Release.