A chief executive rarely calls an accountant because the week is going well. A deal has complicated the tax picture. The insurance renewal landed with an unpleasant number. A finance team cannot close the books quickly enough. A cyber incident has converted an abstract risk into a very concrete meeting. CBIZ built its business around that untidy bundle of middle-market problems. Its answer was not a single star partner or a clever subscription. It was a network: local advisers who know the client, connected to specialists who know the problem.
That proposition sounds almost modest. In practice, it has produced a company with more than 9,500 people across 23 major U.S. markets, six primary service lines and $2.758 billion in 2025 revenue. It also made CBIZ a tidy summary of the professional-services industry's consolidation era. The firm acquired Marcum's non-attest business in November 2024 for roughly $2.3 billion. On July 29, 2026, Grant Thornton Advisors announced an agreement to acquire CBIZ itself for $55 a share in cash, a $5 billion enterprise value.
The useful territory between giant and local
CBIZ occupies a specific patch of ground. Its core customer is more complicated than a small business but may not want the cost, structure or global machinery of the largest firms. Think of a family enterprise preparing for succession, a private equity portfolio company installing adult financial controls, a nonprofit wrestling with regulation, or a construction company whose tax, bonding, benefits and cyber questions arrive at once. These organizations need depth, but they also value an adviser who answers the phone and understands how the company actually operates.
The problems are rarely isolated. A merger produces valuation work, tax diligence, benefits integration and new technology risk. Growth strains payroll and reporting. A tight labor market turns health-plan design into a retention tool. Regulatory changes can touch finance, human resources and data systems in the same quarter. CBIZ's pitch is coordination. A local relationship team diagnoses the issue, then pulls expertise from a national bench. The customer buys judgment by the engagement, retainer, commission or recurring service arrangement rather than buying a piece of software.
What CBIZ packages is not simply expertise. It is the choreography of expertise.The integrated-services thesis
That structure gives CBIZ a practical distinction from both ends of the market. A regional boutique can offer intimacy but may need to refer specialized work elsewhere. A global firm has specialists in abundance but can feel oversized for a midsize client. CBIZ tries to keep the first quality while borrowing the second. The phrase it uses - trusted local advisers enhanced by specialists nationwide - is less a slogan than an operating diagram.
A professional-services flywheel
CBIZ's business model runs on a familiar but powerful loop. Win a relationship in one specialty. Deliver well enough to earn trust. Introduce adjacent expertise when a new problem appears. Add talent and geography through acquisitions. Give acquired practices access to capital, marketing, technology and a broader catalog. The firm gains another entry point; the acquired adviser gains more answers to sell.
The revenue mix reveals where the weight sits. Accounting, tax, advisory and consulting produced about $2.301 billion in 2025, more than four-fifths of the total. Benefits and insurance contributed about $410 million. National practices, including managed networking and hardware services, supplied roughly $47 million. This is a people business: revenue depends on attracting specialists, keeping them busy, pricing their time and preserving the client trust that makes a second assignment possible.
Recurring tax, benefits, insurance and outsourced operations work can anchor a client relationship, while transactions, valuations, forensic assignments and technology projects add episodic revenue. The mix is attractive because regulatory complexity does not retire, payroll keeps running and insurance still renews. Yet it is not automatic. Clients can end many engagements with little notice. Talent is mobile. A cross-sell that feels useful builds the relationship; one that feels like a quota does the opposite.
The Marcum scale jump
Marcum changed the dimensions of the company. Founded in 1951, the New York firm brought more than 3,500 professionals, 43 offices, roughly $1.2 billion in revenue and over 35,000 clients when the deal was announced. Its strengths with entrepreneurial companies, public-company registrants and high-net-worth clients expanded CBIZ's reach and specialist depth. The combination made CBIZ the seventh-largest accounting-services provider in the country.
The financial effect was blunt: 2025 revenue rose 52.1 percent to $2.8 billion, adjusted EBITDA reached $446.9 million and free cash flow reached $175.5 million. The operating task was subtler. Thousands of professionals, overlapping systems, local practices and two corporate histories had to become useful to one another. By February 2026, management said integration was nearly complete, while pointing to growth opportunities in industry specialization, offshoring and artificial intelligence.
A second deal, before the dust settles
Then came the next transaction. Grant Thornton Advisors, backed by New Mountain Capital, agreed to buy CBIZ in cash. If approved and completed as expected in the fourth quarter of 2026, CBIZ will leave the New York Stock Exchange. The combination is expected to create the fifth-largest U.S. professional-services, tax and advisory provider, with a wider multinational reach and more capacity to invest in technology and industry expertise.
One important piece is planned to travel a different route. CBIZ Benefits & Insurance Services is expected to become a separate company backed by New Mountain after closing. That would divide a key element of the six-service model from the accounting and advisory combination. The transaction is not finished: it still requires CBIZ shareholder approval, regulatory clearance and customary closing conditions. Until then, the most accurate tense is future conditional, not victory lap.
The timing makes CBIZ an unusually clear window into its market. Private capital and large firms are hunting scale, technology budgets, specialist talent and recurring client relationships. Local practices face succession questions and rising investment requirements. Middle-market clients increasingly want advice that crosses departmental lines. A platform that can absorb firms without immediately flattening their relationships becomes valuable both as a buyer and, eventually, as a target.
Expertise, with a new operating system
Technology is not a seventh decorative service line. It is beginning to alter how the other six work. In 2026, CBIZ said it had launched AI-enabled tools and market-intelligence capabilities to help professionals identify client opportunities and provide more forward-looking insights. The acquisition of BINDZ added more than 250 professionals in India and a global delivery platform intended to pair offshore talent with AI-enabled workflows. The ambition is familiar across the industry: automate preparation, surface patterns faster and leave expensive human attention for interpretation.
CBIZ also uses research as a product-shaped form of marketing. Its Tradeoff Economy work with Ohio State's Fisher College of Business and the National Center for the Middle Market studies how leaders balance growth, risk and innovation. That material gives advisers a reason to enter a conversation before a tax deadline or transaction forces one. A pooled employer plan launched in July 2026 takes the same approach from another angle, bundling retirement-plan administration and fiduciary support for employers that want less complexity.
The company's mission is plain: provide advice and solutions that help clients achieve their goals. Its five stated values put client success, winning, OneCBIZ, ethical conduct and people in the same frame. Those principles matter most during integration, when the spreadsheet logic of scale meets the social reality of a partnership. A professional-services firm can buy contracts and offices. It cannot simply purchase trust at closing.
The middle market does not need another directory of experts. It needs someone to know which expert enters the room next.The CBIZ position
Where CBIZ fits now
For customers, CBIZ remains useful when a business has outgrown a patchwork of small vendors but still wants advice scaled to its own reality. It can help a buyer diligence an acquisition, a finance chief improve reporting, an employer redesign benefits, a board understand cyber exposure or a family plan a transition. The advantage is strongest when those assignments touch. Information gathered in one corner can sharpen the questions asked in another, subject to professional independence and confidentiality rules.
Competitively, CBIZ sits alongside national firms such as RSM, BDO, Baker Tilly and Grant Thornton, while meeting regional accounting practices, large insurance brokers and specialist consultancies one engagement at a time. Its defense is breadth without complete impersonality. Its challenge is that every acquisition adds scale and integration risk at once. The Marcum deal increased leverage, expanded the organization and demanded a long systems-and-culture merge. The Grant Thornton agreement now proposes an even larger destination.
There is a circular quality to the story. Michael DeGroote founded the platform in 1996 around a belief that smaller growing companies deserved access to a national collection of first-rate specialists. Thirty years later, that collection is preparing to enter a still larger one. The names, owners and reporting lines may change. The customer's Tuesday morning remains stubbornly recognizable: a tax issue, an insurance question, a shaky process, a deal. CBIZ became valuable by making those problems neighbors.