Aon’s third-quarter results show a business performing solidly on every revenue metric that matters. Organic revenue grew 6% in the quarter, with commercial risk and reinsurance each up 7% and health solutions up 6%. Adjusted operating margin expanded 70 basis points to 27.0%. Adjusted earnings per share rose 10% to US$3.36.
The balance sheet is less tidy. Long-term debt stood at US$14.66 billion at the end of 2025. By September 30, it had risen to US$26.32 billion, an increase of approximately US$11.66 billion in nine months. The jump is almost entirely attributable to the financing of Aon’s US$17 billion acquisition of USI Insurance Services from KKR, which is expected to close before the end of the year.
In September, Aon issued US$13.5 billion in senior notes across seven tranches, with maturities running from 2029 to 2056 and coupons ranging from 5.35% to 6.45%. The proceeds are currently sitting in short-term investments on the balance sheet, which jumped from US$1.6 billion to US$13.3 billion over the same period, awaiting the deal’s close. Once USI is absorbed, Aon will have completed two acquisitions totalling approximately US$30 billion in two years, following its US$13 billion purchase of NFP in April 2024.
Aon repurchased no shares in the third quarter despite holding US$7.7 billion of remaining buyback authorisation, and has told investors it will prioritise debt repayment over shareholder returns as it targets a leverage ratio of 2.8x-3.0x within approximately 24 months of the USI close. The dividend continues, but the broader capital return programme is effectively suspended.
The Accelerating Aon United restructuring programme, meanwhile, generated US$93 million in charges in the quarter, up 191% on the same period last year. The programme was launched in 2023 to streamline operations, cut headcount and consolidate real estate.
Aon describes the driver as “primarily costs related to workforce optimisation,” which is headcount reduction. The timing is notable: NFP integration costs were described as “substantially completed” at June 30, and USI has not yet closed. The restructuring charge spike suggests Aon is rationalising its combined workforce across the existing business and NFP simultaneously, ahead of adding USI’s 10,500 staff.
The programme was initially designed to deliver US$350 million in annual savings by end-2026, with total cash charges of approximately US$900 million over three years. Nine-month charges in 2026 already stand at US$281 million.
S&P Global affirmed Aon’s A- issuer credit rating after the USI announcement but moved the outlook to negative, stating that a downgrade remains possible if leverage does not return to its base case within two years of the close. Fitch separately assigned a BBB+ rating to the new senior notes themselves and placed that rating on negative watch. Both signals reflect that Aon is carrying substantially more debt than it has historically, at a moment when it must also integrate two major acquisitions and retain the broker talent that makes both businesses valuable.
According to KKR, USI’s revenue nearly tripled under its nine-year ownership through a combination of organic growth and more than 90 acquisitions. Retaining that network through a change of ownership and integration with NFP is the execution risk S&P and Fitch both flag in their ratings commentary.
Aon frames USI as the next stage of the same middle-market thesis it deployed with NFP: buying a PE-backed broker platform and integrating it onto Aon’s shared services and analytics infrastructure. The deal is expected to dilute adjusted EPS in 2027 before turning accretive in 2028, with US$395 million in projected annual run-rate synergies.
The operating results that fund all of this remain strong. Commercial risk segment's organic growth of 7% in the quarter was driven by North America and EMEA, with M&A services and core P&C performing particularly well. Reinsurance organic growth of 7% reflected strong treaty placements, though net market impact was unfavourable as pricing continues to soften.
Health solutions grew 6% organically, with particular strength internationally. Wealth solutions grew 4%, with demand for UK and EMEA retirement advisory work linked to ongoing regulatory change providing a consistent tailwind.
Total revenue for the nine months reached US$13.38 billion, up 4%. Free cash flow for the same period was US$1.94 billion.
“Our Aon United strategy continues to advance and differentiate our platform for clients,” said Greg Case, president and chief executive. “We enter the fourth quarter with significant momentum, reinforcing confidence in our ongoing ability to deliver sustained, differentiated performance.”
The fourth quarter is when all the deferred consequences land at once: the USI close, the debt on the books, the integration beginning and the first real test of whether the synergy projections survive contact with reality.
