Grant Thornton US announced on Wednesday, July 29, 2026, its acquisition of CBIZ in a significant $5 billion deal. This acquisition positions the combined entity as the seventh-largest accounting services provider in the U.S., boasting approximately $2.8 billion in annual revenues. The transaction is expected to close later this year, pending standard closing conditions.
This move follows Grant Thornton's strategy to expand its advisory services. Earlier, Grant Thornton US had acquired French, Spanish, and Belgian member firms, as reported on July 29, 2026. Additionally, a separate but related development saw Grant Thornton's advisory practice joining forces with Auxis, a nearshore pioneer, which will integrate Auxis's 1,400 team members primarily located in Costa Rica and Colombia.
Simultaneously, CBIZ, a professional services advisor to middle-market businesses, separately announced on July 31, 2024, that it would acquire the non-attestation services business of accounting firm Marcum in a $2.3 billion deal. This cash-and-stock transaction, which was finalized on November 1, 2024, involved approximately half the consideration in cash and the remainder in CBIZ common stock. Marcum's attest business was acquired by Mayer Hoffman McCann P.C., a firm with a long-standing administrative service agreement with CBIZ.
The strategic rationale behind the Grant Thornton-CBIZ merger, as well as CBIZ's prior acquisition of Marcum's non-attest business, centers on solidifying market positions, accelerating growth, attracting top talent, and enhancing client offerings. The combined entity is poised to offer a broader array of high-value solutions to a client base of over 135,000, supported by more than 10,000 team members across various financial, insurance, and advisory services. Analysts had previously urged CBIZ to pursue mergers and acquisitions, and the company's recent activities reflect a strong pursuit of inorganic growth.
