Aon plc announced it has signed a definitive agreement to acquire USI from KKR and other shareholders for a total purchase price of $17.0 billion.

“Combining with USI will establish the premier U.S. middle-market platform, deepen our context advantage and position Aon to accelerate organic growth,” said Greg Case, President and CEO of Aon, in a statement.

“Building on the success of our acquisition of NFP, USI will substantially enhance our middle-market footprint and expand access for our firm in the E&S segment to deliver content, capabilities and expertise to a broader client base, while enabling client leaders to expand relationships and win new business,” Case added. “Our combined data platform will generate richer insight, advance the development of innovative, AI-driven solutions and expand the universe of insurable risk, while further reinforcing the context advantage that differentiates Aon.”

Following the close of the transaction, USI Chairman and CEO Mike Sicard will serve as President of Aon plc and global CEO of Middle Market, reporting to Case, and join the Aon Executive Committee.

According to Aon, the transaction:

Establishes the leading platform in the large and growing U.S. middle-market segment. The addition of USI substantially enhances Aon’s presence in the more than $40 billion U.S. middle-market segment. The acquisition will also extend Aon’s capabilities across health, talent and Human Capital advisory offerings to provide better choice, superior solutions and greater value for clients.

Expands Aon’s direct access to the E&S segment, distributed through Managing General Agents, Managing General Underwriters and Wholesalers. USI’s emerging wholesale capabilities will strengthen Aon’s ability to meet a wider range of client needs and meaningfully participate in the E&S segment.

Enhances Aon’s industry-leading data platform, deepening its context advantage. The transaction will expand Aon’s data ecosystem and augment the firm’s proprietary data flow, fidelity and analytics to generate richer insights and deliver differentiated, AI-enabled solutions and drive better client outcomes.

Unites organizations with shared one-firm mindsets and proven leadership teams, facilitating a faster, more seamless integration and greater value capture. Powered by its proprietary USI ONE® platform for analytics, USI is highly complementary with Aon’s one-firm, Aon United strategy and global Aon Business Services operating and technology engine.

Creates compelling long-term shareholder value with significant synergies, enhanced growth opportunities and larger addressable markets. The combination is expected to accelerate organic growth across Aon’s middle-market platform by enhancing client access to value-added capabilities. Building on the firm’s demonstrated success in integrating NFP, Aon has a clear path to deliver approximately $395 million in annual run-rate net adjusted EBITDA impact from identified revenue and cost synergies across the combined middle-market platform. Aon expects the acquisition to be accretive to adjusted EPS in 2028 and thereafter.

Transaction Details

The purchase price for USI is $17.0 billion, or $16.7 billion on a net basis, which reflects approximately $278 million of certain tax attributes. The net purchase price represents approximately 14.5x on a synergized trailing 12-month adjusted EBITDA basis.

Aon expects to fund the transaction, as well as related transaction expenses and other costs, with new debt raised across a range of maturities, subject to market conditions.

The firm expects to maintain its current rating of Baa2 with Moody’s and A- with S&P. Aon will continue to execute its disciplined capital allocation strategy, prioritizing de-leveraging, funding a stable and growing dividend and balancing investments for growth with return of excess capital. Consistent with this strategy, the firm does not expect to repurchase shares in the near-term as it prioritizes debt repayment.

The transaction has been unanimously approved by the Board of Directors of Aon and the Board of Directors of USI. Closing of the transaction is subject to customary conditions, including regulatory approvals, and is expected to occur in the fourth quarter of 2026. Aon and USI will continue to operate independently until the closing date.

BofA Securities and Citi served as financial advisors to Aon on the transaction. Cravath, Swaine & Moore LLP acted as legal counsel to Aon, McDermott Will & Schulte LLP acted as legal advisor to Aon with respect to regulatory matters and Skadden, Arps, Slate, Meagher & Flom is acting as financing counsel to Aon.