Aon strikes $17 billion deal for rival USI as insurance consolidation accelerates

Insurance giant Aon announced on Monday its acquisition of U.S. Insurance Services (USI), a rival broker, for $17 billion, marking one of the largest deals in recent years. This acquisition comes as part of a wave of mega buyouts in the insurance brokerage industry, driven by companies' desire to strengthen their market position and competitive edge.

Aon CEO Greg Case highlighted the strategic importance of the USI acquisition, stating that it will significantly bolster Aon's presence in the U.S. middle-market insurance segment, which serves mid-sized businesses and is characterized by rapid growth in the excess & surplus (E&S) sector.

The E&S segment is one of the fastest-growing areas in U.S. commercial insurance, representing a significant portion of direct written premiums. The $17 billion deal builds upon Aon's $13 billion acquisition of NFP in 2024 and will expand its health, talent, and human capital advisory services. Founded in 1994, USI began as a single office and has since grown to become the tenth largest U.S. insurance brokerage, with an annual revenue of approximately $3 billion.

This acquisition follows other significant deals in the insurance brokerage sector, such as Arthur J. Gallagher's $13.5 billion purchase of AssuredPartners and Brown & Brown's $10 billion acquisition of Accession Risk Management. KKR, the private equity firm behind USI, has been actively selling off its portfolio companies, achieving record monetization in the second quarter, the largest in the firm's history.

Under the terms of the agreement, Aon will finance the deal through debt and has no immediate plans for share buybacks, prioritizing debt repayment instead. USI CEO Mike Sicard will join Aon as the president and global CEO of its middle-market platform. The acquisition is expected to close in the fourth quarter of 2026 and is anticipated to enhance Aon's adjusted profit in 2028. The deal is being advised by BofA Securities, Citi, Goldman Sachs, Insurance Advisory Partners, and Morgan Stanley.