The U.S. accounting industry is getting another major shake-up. Grant Thornton Advisors has agreed to acquire CBIZ in a $5 billion all-cash transaction, creating the fifth-largest accounting, tax and advisory firm in the United States. The deal is another sign that scale has become a strategic priority for firms looking to compete beyond the Big Four.
A Bigger Platform for the Mid-Market
CBIZ shareholders will receive $55 per share, representing a premium of nearly 18% over the company’s previous closing price. Once completed, the combined business is expected to generate more than $7.5 billion in annual revenue and operate across over 20 countries and territories.
For Grant Thornton, the acquisition significantly strengthens its presence in the U.S. middle market while expanding its tax, accounting, consulting and advisory capabilities.
Consolidation Continues Across the Profession
The transaction is part of a broader trend transforming the accounting industry. Mid-market firms are combining to build larger platforms, invest in technology and broaden the range of services they can offer clients.
Grant Thornton itself has been expanding rapidly since receiving backing from New Mountain Capital in 2024, with the investment firm providing additional equity to support the CBIZ acquisition.
What Happens Next?
The companies expect the transaction to close during the fourth quarter of 2026, subject to shareholder and regulatory approvals. Following completion, CBIZ’s benefits and insurance division will be separated into an independent company backed by New Mountain Capital.
CBIZ also has a “go-shop” period running until 27 August 2026, allowing it to consider any competing acquisition proposals.
Why This Matters
The race for scale in professional services is accelerating. As clients demand broader advisory capabilities, greater technology investment and international reach, mergers are becoming one of the fastest ways for firms to expand.
If completed, the Grant Thornton-CBIZ combination will create one of the largest professional services platforms outside the Big Four and further reshape the competitive landscape of the U.S. accounting market.