CBIZ to be taken private by Grant Thornton in largest US accounting M&A in 25+ years

Grant Thornton Advisors LLC has entered into a definitive merger agreement to acquire CBIZ, Inc. (NYSE: CBZ) in an all-cash transaction with an enterprise value of $5 billion, backed by additional equity from Grant Thornton’s private-equity investor New Mountain Capital. CBIZ shareholders will receive $55.00 in cash per share, representing an approximate 54% premium to CBIZ’s 30-day volume-weighted average share price and roughly 17.8% above the last close before the announcement. The transaction is expected to close in the fourth quarter of 2026, subject to CBIZ shareholder approval, regulatory clearances and other customary closing conditions, with a go-shop window running until 11:59 PM Eastern Time on 27 August 2026. It is the largest public-accounting transaction in over 25 years, and the combined firm is expected to become the fifth-largest US professional services provider by domestic revenue. The tension for investors sits between a generous headline premium and the operating slippage CBIZ disclosed on the same day, alongside a structural rearrangement that removes the only publicly listed US accounting firm from public markets.

What does the Grant Thornton Advisors agreement to acquire CBIZ change about the mid-tier US professional services landscape?

The combination pulls two of the ten largest US accounting-and-advisory firms into a single organisation and reshapes the tier immediately below the Big Four. Grant Thornton Advisors currently ranks ninth on the Accounting Today 2026 Top 100 Firms list with about $2.5 billion in annual revenue. CBIZ ranks eighth with roughly $2.8 billion. On completion, Grant Thornton Advisors would operate across more than 20 countries and territories, carry approximately $5 billion in annual US revenue and close to $7.5 billion globally, and count more than 34,500 professionals across the Americas, Europe, the Middle East and the Asia-Pacific region.

That scale still leaves the combined firm well below Deloitte, PricewaterhouseCoopers, Ernst & Young and KPMG in the United States, but it materially widens the gap between the new number five and the remaining mid-tier firms. For mid-market clients that historically chose between a Big Four relationship and a mid-tier alternative, the choice set narrows. For talent, career-path economics inside the combined firm now compete with Big Four ladders in a way neither Grant Thornton nor CBIZ could offer independently. The immediate strategic argument is scale efficiency, cross-selling reach into the middle market, and platform investment capacity for artificial intelligence and industry-specific advisory build-outs.

Why does the $5 billion enterprise value and 54% premium sit well above CBIZ’s prior analyst price targets?

The $55.00 cash consideration is a significant step-up against most external reference points other than CBIZ’s recent trading. It compares with a BMO Capital price target of $33.00 dated 30 March 2026 and a $31.00 target set by another sell-side firm on 10 April 2026. Against those anchors, Grant Thornton Advisors is paying between roughly 67% and 77% above what covering analysts considered fair value only months before the deal. Against CBIZ’s 30-day volume-weighted average share price, the premium is 54%. Against the last close before the announcement, the premium narrows to 17.8%, reflecting the run-up in CBIZ shares in the weeks preceding the deal.

The enterprise-value math also stands out against CBIZ’s disclosed operating profile. Adjusted EBITDA in the second quarter of 2026 was $103.1 million, down 14.3% year on year. Even generously annualising a stronger recent quarter, the deal implies an EBITDA multiple in the low to mid-teens for a business whose operating margin fell to 5% from 9.7% a year earlier. Grant Thornton Advisors and New Mountain Capital are pricing the transaction on medium-term integration value and platform economics, not on a straight-line extrapolation of the most recent quarter.

How does the take-private thesis intersect with CBIZ’s second-quarter operating slippage and ongoing Marcum integration?

CBIZ released second-quarter and first-half 2026 results on the same day as the acquisition announcement and simultaneously cancelled its planned conference call and webcast. Second-quarter revenue was $682.2 million, essentially flat year on year and about 2.3% below the FactSet consensus of $698.0 million. GAAP net income fell to $18.6 million from $41.9 million, and GAAP diluted earnings per share dropped to $0.31 from $0.66, a 53.0% decline. Adjusted diluted earnings per share came in at $0.91, beating the $0.72 consensus, and adjusted EBITDA of $103.1 million exceeded the $94.0 million consensus. However, adjusted EBITDA still fell 14.3% year on year, and operating margin nearly halved from 9.7% to 5.0%.

For the first half, revenue was $1.53 billion, up 0.6%, net income rose 4.1% to $171.4 million, and free cash flow was $110.5 million. Net leverage sat at 3.4 times. Chief Executive Officer Jerry Grisko attributed the softer profit trajectory to continued investment in integrating Marcum LLP, which CBIZ acquired in November 2024 for approximately $2.3 billion in cash and stock, alongside spending on artificial-intelligence capabilities and go-to-market changes. CBIZ withdrew its 2026 outlook in connection with the merger announcement.

Read together, the results and the deal are difficult to separate. A public CBIZ heading into the second half with declining EBITDA, a 5% operating margin, and a still-active integration would have faced a testing narrative through the remainder of the year. A private CBIZ inside Grant Thornton Advisors can absorb integration costs from two large combinations, Marcum and Grant Thornton, without quarterly guidance pressure or a public share price that reflects every non-cash step. Whether that shelter accelerates or delays operating recovery is now a question for New Mountain Capital and the combined management team rather than public shareholders.

What does the Benefits and Insurance Services carve-out signal about New Mountain Capital’s post-close strategy?

The transaction is not a straight full-firm acquisition. Grant Thornton Advisors intends to separate CBIZ’s Benefits and Insurance Services segment into a stand-alone company backed by New Mountain Capital after the deal closes. Benefits and Insurance Services provides brokerage and consulting across group health, property and casualty insurance, retirement plan advisory, payroll, human capital management, actuarial services and life insurance, and it has historically sat alongside CBIZ’s Financial Services and National Practices groups.

Separating that segment produces two distinct enterprises with different economics, different regulatory footprints and different exit paths. The core Grant Thornton–CBIZ combination becomes a focused professional services firm around accounting, tax and advisory, aligned to Grant Thornton’s existing platform. The Benefits and Insurance Services company becomes a stand-alone insurance-and-benefits distribution business with its own capital structure and its own eventual monetisation path. New Mountain Capital retains sponsorship of both. For investors watching how private equity is reshaping the middle of the professional services industry, the structure is a template. The buyer is not simply consolidating; it is unbundling adjacent businesses that trade at different multiples and require different investment cadences.

Why do the go-shop period and termination fee structure matter for arbitrage traders and any rival bidder?

CBIZ can actively solicit alternative acquisition proposals during a go-shop period ending 11:59 PM Eastern Time on 27 August 2026, after which customary no-shop restrictions apply. The merger agreement includes a $107.5 million company termination fee payable by CBIZ to Grant Thornton Advisors in specified termination scenarios, reduced to $49.6 million if CBIZ terminates during the go-shop window or in favour of an Excluded Party superior proposal. A $198.4 million parent termination fee runs the other way in certain failure-to-close or breach circumstances, supported by a limited guarantee from Grant Thornton Advisors LLC. Grant Thornton has $5.2 billion in committed financing, comprising both equity from New Mountain Capital and debt.

The reduced go-shop break fee is the most economically material of these numbers for a rival bidder. A challenger emerging by 27 August 2026 would face a $49.6 million cost of displacing Grant Thornton Advisors, roughly one percent of enterprise value. That is a low friction point on paper, but the 54% premium to the 30-day volume-weighted average and the specialised nature of professional services combinations make an incremental higher bid difficult to structure. CBIZ shares closed at $54.90 on 29 July 2026, up 17.56% on the day, the largest single-day gain since 2003, and traded around $54.45 in early activity the following morning. The arbitrage spread of roughly 55 cents, or about 1.0%, is consistent with the market assigning high probability to the deal closing at $55.00 and low probability to a rival bid clearing the go-shop.

How does the combined firm sit against the Big Four and the rest of the accounting stack after close?

Grant Thornton Advisors’s own framing places the combined firm fifth in the United States by domestic revenue, meaningfully behind Deloitte, PricewaterhouseCoopers, Ernst & Young and KPMG but well ahead of the next tier of national firms. The combined workforce of 34,500-plus professionals still trails each of the Big Four by a large multiple, but the revenue-per-professional profile of a scaled advisory-heavy firm can be a competitive lever in tax, transaction advisory, valuation, risk and technology consulting where the Big Four sometimes face independence constraints tied to their audit relationships.

For competitors including BDO USA, RSM US, Baker Tilly, Crowe and Cherry Bekaert, the message is that private-equity-backed roll-up capital can build a genuine fifth pole in a single transaction rather than through years of tuck-ins. The next competitive question is whether any of those firms responds with its own private-equity partnership or transformational combination, and whether the Big Four adjust their middle-market pricing to defend share against a larger and better-capitalised alternative. The strategic argument from Chief Executive Officer of Grant Thornton Advisors Jim Peko emphasises multinational reach combined with CBIZ’s middle-market density; the practical test is whether the combined firm can retain revenue and partners through what will be an unusually complex integration overlapping the still-active Marcum absorption.

What does removing the only publicly listed US accounting firm mean for market visibility into the industry?

CBIZ was the only publicly traded US accounting services firm on the New York Stock Exchange. On close, CBIZ common stock will cease to trade and will be delisted, and the combined firm will operate wholly inside a private-equity-sponsored structure. Public disclosure about the economics of large US accounting-and-advisory firms will effectively contract to whatever the Big Four and their limited liability partnerships choose to release, plus any regulatory filings tied to specific engagements or credit facilities.

For institutional investors, regulators, journalists and the professional services industry itself, that reduces the ability to benchmark realisation rates, utilisation, partner economics, integration costs and margin trajectory against a listed comparable. It also removes the only equity vehicle through which public-market capital could directly participate in the growth of a US accounting-and-advisory firm. Whether the combined Grant Thornton Advisors–CBIZ eventually re-enters public markets through an initial public offering, or remains a private-equity holding until an exit to another sponsor or a strategic buyer, will be a defining question for the next phase of professional services consolidation. Under standard private-equity holding periods, a potential re-listing or secondary sale is a multi-year story, not an immediate outcome.

What should investors track as Grant Thornton Advisors and CBIZ move the $5 billion cash deal toward Q4 2026 completion?

• Grant Thornton Advisors has entered into a definitive merger agreement to acquire CBIZ in an all-cash transaction with an enterprise value of $5 billion, at $55.00 per share, backed by additional New Mountain Capital equity and $5.2 billion in aggregate committed financing.
• The $55.00 cash price is a 54% premium to CBIZ’s 30-day volume-weighted average share price, 17.8% above the last close, and roughly 67% to 77% above pre-deal sell-side price targets in the low-$30s range.
• CBIZ closed at $54.90 on 29 July 2026, up 17.56%, the largest single-day gain since 2003; the roughly 1% residual spread to the $55.00 offer implies the market assigns a high probability to the deal completing at the announced terms.
• Second-quarter 2026 results released the same day showed revenue essentially flat at $682.2 million, a 2.3% miss to consensus, GAAP earnings per share down 53.0% to $0.31, and adjusted EBITDA down 14.3% to $103.1 million, with 2026 outlook withdrawn; the operating trajectory strengthens the rationale for a private-market integration horizon.
• CBIZ’s Benefits and Insurance Services segment is planned to be separated post-close into a stand-alone company backed by New Mountain Capital, indicating a deliberate two-business outcome rather than a single combined entity.
• Combined pro forma scale of more than $5 billion US revenue, close to $7.5 billion global revenue, more than 34,500 professionals and operations across 20-plus countries would create the fifth-largest US professional services provider, behind only Deloitte, PricewaterhouseCoopers, Ernst & Young and KPMG.
• The transaction includes a go-shop period ending 27 August 2026, a $49.6 million reduced company termination fee inside the go-shop window rising to $107.5 million afterwards, and a $198.4 million parent termination fee; the low reduced fee lowers the theoretical hurdle for a challenger, though the 54% premium and industry structure make a rival bid unlikely.
• Marcum LLP integration remains active from the November 2024 combination, and Chief Executive Officer of CBIZ Jerry Grisko cited related investment as a driver of near-term margin compression; overlapping this with the Grant Thornton combination introduces meaningful execution risk that private ownership is intended to absorb.
• Closing is expected in the fourth quarter of 2026 subject to CBIZ shareholder approval and regulatory clearances; the near-term catalysts are the go-shop expiry on 27 August, the shareholder proxy vote and any antitrust review commentary.
• On completion, CBIZ will delist from the New York Stock Exchange, ending public-market visibility into the only listed US accounting-and-advisory firm and leaving industry economics observable primarily through Big Four disclosures, private-equity commentary and regulatory filings.