AON: Material agreement · Termination of an agreement · New financial obligation

Item 1.01 Entry into a Material Definitive Agreement Term Loan Credit Agreement On September 18, 2026, Aon plc, an Irish public limited company (the “Company”), Aon Corporation, a Delaware corporation (“Aon Corporation”), Aon Global Holdings plc, a public limited company organized under the laws of England and Wales (“AGH”), Aon Global Limited, a private limited company organized under the laws of England and Wales (“AGL”), and Aon North America, Inc., a Delaware corporation (“ANA”), entered into a Credit Agreement (the “Term Loan Credit Agreement”), with Citibank, N.A. (“Citibank”), as administrative agent, and the lenders party thereto from time to time (collectively, the “Term Lenders”), pursuant to which the Term Lenders committed to provide unsecured delayed draw term loan facilities in an aggregate principal amount of $4,000,000,000, consisting of (a) a two-year $2,000,000,000 term loan facility (the “Tranche 1 Term Loans”) and (b) a three-year $2,000,000,000 term loan facility (the “Tranche 2 Term Loans”, and together with the Tranche 1 Term Loans, the “Term Loans”). The Term Loans will be available, subject to customary limited conditionality for a financing transaction of this type, to ANA as borrower, on the closing date of the previously announced acquisition by ANA of USI Advantage Corp. (“USI” and such acquisition, the “USI Acquisition”) pursuant to the agreement and plan of merger, dated as of August 30, 2026 (the “Merger Agreement”), entered into by and among the Company, ANA, USI, Cortlandt Acquisition Corp., a Delaware corporation, and, solely in its capacity as the securityholder representative, Uno Aggregator II L.P., a Delaware limited partnership. The proceeds of the Term Loans will be used to pay a portion of the cash consideration with respect to