Aon agrees to pay $17 billion in cash for USI, if the merger closes

Aon has a signed merger agreement for USI. It does not have USI yet.

That is the 8-K cash price. The Dublin press release is Aon’s case for what the combination is supposed to become: a larger U.S. middle-market broker on top of Aon’s 2024 NFP purchase, with more Excess & Surplus reach. Leadership titles in that release sit after a close.

The cash, and the other cash numbers

The 8-K does not print $17.0 billion. It prints $17 billion in cash, then points at leakage in the merger agreement.

Exhibit 99.1 is more promotional and more precise in a different way. It calls the purchase price $17.0 billion, “or $16.7 billion on a net basis, which reflects approximately $278 million of certain tax attributes.” That net figure is Aon’s presentation of tax attributes. It is not the leakage mechanic in the 8-K.

The agreement itself, Exhibit 2.1, sets Per Share Merger Consideration at $57.50 in cash, minus each share’s portion of any closing leakage amount. The locked-box date in that contract is June 30, 2026 — the date of USI, Inc.’s unaudited quarter-end balance sheet. The 8-K does not print a share count that would turn $57.50 into $17 billion.

Aon also says the net purchase price is about 14.5 times “synergized” trailing twelve-month adjusted EBITDA. That multiple is the company’s non-GAAP framing. The release’s own non-GAAP note says synergized adjusted EBITDA is a management estimate, not Regulation S-X pro forma. The release does not print the EBITDA behind that 14.5 times.

Who USI is, as Aon describes it

USI, in the release, is a U.S. property-and-casualty, employee-benefits, personal-risk, and retirement broker. Aon calls it the tenth-largest U.S. insurance broker, with about $3 billion in annual revenue, more than 10,500 people, and nearly 200 U.S. offices, headquartered in Valhalla, New York. Those are Aon’s and USI’s figures and ranking.

Sellers, in the press release, are “KKR and other shareholders.” The merger agreement’s definition of Sponsors is more specific: KKR & Co. Inc., Caisse de dépôt et placement du Québec, and Integrum Holdings LP, with their affiliates. The exhibits do not print ownership percentages.

The structure is ordinary Delaware merger math. Cortlandt Acquisition Corp. merges into USI Advantage Corp. USI continues as the surviving corporation. Retail investors are not being asked to tender. Aon Class A ordinary shares stay listed on the NYSE under AON.

Aon says it will fund the purchase, and related costs, with new debt across a range of maturities, subject to market conditions. It says it expects to keep its current Moody’s Baa2 and S&P A- ratings, and that it does not expect to repurchase shares in the near term while it pays debt down. Those are Aon’s expectations. They are not rating-agency actions.

What Aon says the combination is for

The strategic pitch is middle market and Excess & Surplus, plus data.

Aon says USI “substantially enhances” its presence in a U.S. middle-market segment it sizes at more than $40 billion, and more than one third of U.S. commercial property-and-casualty direct written premium. It says USI’s “emerging wholesale capabilities” widen access to E&S, which it calls among the fastest-growing areas in U.S. commercial insurance and 26% of U.S. commercial P&C premiums. Those market shares are Aon’s characterizations.

The financial pitch is a synergy number. Aon says it has “a clear path” to approximately $395 million in annual run-rate net adjusted EBITDA impact from identified revenue and cost synergies across the combined middle-market platform, and that it expects the acquisition to be accretive to adjusted EPS in 2028 and thereafter. Approximately $395 million is the company’s claim. The release does not phase it or split cost from revenue, and 2028 accretion is not a result.

Mike Sicard’s new titles sit in the same contingent bucket. USI’s chairman and chief executive, the release says, will serve as President of Aon plc and global CEO of Middle Market following close, report to Greg Case, and join the Aon Executive Committee. Until close, Aon and USI “will continue to operate independently.”

What still has to happen

Both boards unanimously approved the deal, Aon said. Closing still needs the conditions in Article VII of the merger agreement.

Shared conditions include stockholder approval; no law making the merger illegal and no governmental order prohibiting it; expiration or termination of Hart-Scott-Rodino waiting periods; insurance-law consents listed on a disclosure schedule that is not in the public exhibit; and a FINRA continuing-membership path for USI’s broker-dealer — either written approval of the CMA, or the Rule 1017 route the contract spells out if FINRA has not imposed material restrictions.

The parties are not required to close before the Inside Date, which the agreement defines as October 19, 2026, or December 18, 2026 if specified auditor or comfort-letter conditions fail. Aon’s release still says it expects to close in the fourth quarter of 2026.

If the merger is still open on June 1, 2027, at 5:00 p.m. New York time, either side may terminate — with two automatic three-month extensions if the competition-law or HSR-related conditions remain unsatisfied.

Aon will host a conference call August 31, 2026, from 8:00 to 8:45 a.m. Eastern, with slides at ir.aon.com.

The next fact that would change the object is a close — or a filing that says the conditions will not be met.