Aon Plc sold $13.5 billion of investment-grade bonds on Monday to help finance its $17 billion cash acquisition of USI Insurance Services, drawing $65 billion of investor orders for one of the year’s largest M&A financing packages. The seven-tranche offering spans maturities from three to 30 years, with the longest tenor pricing at 115 basis points over Treasuries after initial guidance tightened by 35 basis points.
Market backdrop deteriorates
The deal landed as credit spreads widened and equities slipped following a public appeal from leading artificial-intelligence executives to pause development of the technology. A simultaneous jump in oil prices added to inflation anxiety ahead of Wednesday’s Federal Reserve rate decision, giving underwriters a more volatile window than the syndicate desk would have preferred.
Terms and safeguards
All notes except the 30-year carry a special mandatory redemption at 101 cents on the dollar plus accrued interest if the USI transaction fails or remains unclosed past December 1, 2027. Aon also plans a $4 billion term loan to complete the financing, according to S&P Global Ratings. The acquisition, agreed last month with KKR and other USI shareholders, is targeted for a year-end close and aims to deepen Aon’s reach among midsized corporate clients.
Rating pressure immediate
Fitch Ratings placed Aon on Rating Watch Negative on Monday, stating the purchase will “materially increase credit risk for at least the next two years.” The agency projects leverage climbing to about four times earnings by the close of 2027, a level that leaves little cushion for a broker already carrying significant debt.
Supply calendar stays crowded
Monday’s offering ranks as the second-largest high-grade M&A bond this year, behind only Abbott Laboratories’ $20 billion February deal. Dealers estimate roughly $55 billion of investment-grade supply will hit the market this week, following last week’s $67.6 billion, the fourth-heaviest weekly volume of 2026.