SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	6 Months Ended
Jun. 30, 2026
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Selected Terms Used in Notes to the Condensed Consolidated Financial Statements ASA – Administrative Service Agreement ASC – Accounting Standards Codification ASU – Accounting Standards Update CPA firm – Certified Public Accounting firm FASB – The Financial Accounting Standards Board GAAP – United States Generally Accepted Accounting Principles SOFR – Secured Overnight Financing Rate SEC – United States Securities and Exchange Commission Marcum Transaction – On November 1, 2024, the Company completed the acquisition of Marcum LLP (“Marcum”), an accounting and advisory services firm headquartered in New York City with offices in major markets throughout the United States, to expand the breadth and depth of the Company’s professional services portfolio in the U.S. Pursuant to the Agreement and Plan of Merger dated July 30, 2024 (the “Marcum Merger Agreement”), a wholly owned subsidiary of the Company, merged with and into Marcum Advisory Group, a wholly owned subsidiary of Marcum ("MAG"), to which Marcum contributed substantially all of its non-attest business assets and liabilities, (the “Merger”), resulting in MAG surviving the Merger and becoming a wholly owned subsidiary of the Company. In a separate transaction, CBIZ CPAs P.C., with which the Company has an existing ASA, purchased from Marcum substantially all of Marcum’s attest business assets, subject to certain exclusions (the "Attest Purchase"). As noted in Note 1, Basis of Presentation and Significant Accounting Policies included in our Annual Report on Form 10-K for the year ended December 31, 2025, as amended, the Company does not consolidate certain CPA firms with whom we maintain ASAs, including CBIZ CPAs P.C., therefore, the Merger solely is referred to herein as the “Marcum Transaction.” Description of Business: CBIZ, Inc. is a leading professional services advisor to middle-market businesses nationwide. With industry knowledge and expertise in accounting, tax, advisory, benefits, insurance, and technology, CBIZ delivers actionable insights to help clients anticipate what is next and discover new ways to accelerate growth to clients throughout the United States and parts of Canada. Acting through its subsidiaries, it serves small and medium-sized businesses, as well as individuals, governmental entities, and not-for-profit enterprises.CBIZ manages and reports its operations along two practice groups: Financial Services Group and Benefits and Insurance Services Group. A further description of products and services offered by each of the practice groups is provided in Note 15, Segment Disclosures. Basis of Consolidation: The accompanying unaudited condensed consolidated financial statements include the operations of CBIZ, Inc. and all of its wholly-owned subsidiaries after elimination of all intercompany balances and transactions. We have determined that our relationship with certain CPA firms with which we maintain ASAs qualify as variable interest entities ("VIEs"), and we are the primary beneficiary of such VIEs. The accompanying unaudited condensed consolidated financial statements do not reflect the operations or accounts of the VIEs as the impact is not material to the financial condition, results of operations, or cash flows of CBIZ. Unaudited Interim Financial Statements: The unaudited condensed consolidated financial statements have been prepared in accordance with GAAP and applicable rules and regulations of the SEC regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. As such, the information included in this Quarterly Report on Form 10-Q should be read in conjunction with the consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K, as amended, for the year ended December 31, 2025. In the opinion of CBIZ management, the accompanying unaudited condensed consolidated financial statements reflect all normal recurring adjustments necessary to present fairly the financial condition, results of operations, and cash flows for the interim periods presented, but are not necessarily indicative of the results of operations to be anticipated for the full year ending December 31, 2026. Use of Estimates: The preparation of unaudited condensed consolidated financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the amounts reported and disclosed in the financial statements and the accompanying notes. Changes in circumstances could cause actual results to differ materially from these estimates. Changes in Accounting Policies: We have consistently applied the accounting policies for the periods presented as described in Note 1, Basis of Presentation and Significant Accounting Policies, to the consolidated financial statements contained in our Annual Report on Form 10-K, as amended, for the year ended December 31, 2025.

Marcum Transaction – On November 1, 2024, the Company completed the acquisition of Marcum LLP (“Marcum”), an accounting and advisory services firm headquartered in New York City with offices in major markets throughout the United States, to expand the breadth and depth of the Company’s professional services portfolio in the U.S. Pursuant to the Agreement and Plan of Merger dated July 30, 2024 (the “Marcum Merger Agreement”), a wholly owned subsidiary of the Company, merged with and into Marcum Advisory Group, a wholly owned subsidiary of Marcum ("MAG"), to which Marcum contributed substantially all of its non-attest business assets and liabilities, (the “Merger”), resulting in MAG surviving the Merger and becoming a wholly owned subsidiary of the Company. In a separate transaction, CBIZ CPAs P.C., with which the Company has an existing ASA, purchased from Marcum substantially all of Marcum’s attest business assets, subject to certain exclusions (the "Attest Purchase"). As noted in Note 1, Basis of Presentation and Significant Accounting Policies included in our Annual Report on Form 10-K for the year ended December 31, 2025, as amended, the Company does not consolidate certain CPA firms with whom we maintain ASAs, including CBIZ CPAs P.C., therefore, the Merger solely is referred to herein as the “Marcum Transaction.”

Description of Business: CBIZ, Inc. is a leading professional services advisor to middle-market businesses nationwide. With industry knowledge and expertise in accounting, tax, advisory, benefits, insurance, and technology, CBIZ delivers actionable insights to help clients anticipate what is next and discover new ways to accelerate growth to clients throughout the United States and parts of Canada. Acting through its subsidiaries, it serves small and medium-sized businesses, as well as individuals, governmental entities, and not-for-profit enterprises.CBIZ manages and reports its operations along two practice groups: Financial Services Group and Benefits and Insurance Services Group. A further description of products and services offered by each of the practice groups is provided in Note 15, Segment Disclosures.

Basis of Consolidation: The accompanying unaudited condensed consolidated financial statements include the operations of CBIZ, Inc. and all of its wholly-owned subsidiaries after elimination of all intercompany balances and transactions. We have determined that our relationship with certain CPA firms with which we maintain ASAs qualify as variable interest entities ("VIEs"), and we are the primary beneficiary of such VIEs. The accompanying unaudited condensed consolidated financial statements do not reflect the operations or accounts of the VIEs as the impact is not material to the financial condition, results of operations, or cash flows of CBIZ.

Unaudited Interim Financial Statements: The unaudited condensed consolidated financial statements have been prepared in accordance with GAAP and applicable rules and regulations of the SEC regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. As such, the information included in this Quarterly Report on Form 10-Q should be read in conjunction with the consolidated financial statements and accompanying notes included in our Annual Report on Form 10-K, as amended, for the year ended December 31, 2025.

In the opinion of CBIZ management, the accompanying unaudited condensed consolidated financial statements reflect all normal recurring adjustments necessary to present fairly the financial condition, results of operations, and cash flows for the interim periods presented, but are not necessarily indicative of the results of operations to be anticipated for the full year ending December 31, 2026.

Use of Estimates: The preparation of unaudited condensed consolidated financial statements in conformity with GAAP requires us to make estimates and assumptions that affect the amounts reported and disclosed in the financial statements and the accompanying notes. Changes in circumstances could cause actual results to differ materially from these estimates.

Changes in Accounting Policies: We have consistently applied the accounting policies for the periods presented as described in Note 1, Basis of Presentation and Significant Accounting Policies, to the consolidated financial statements contained in our Annual Report on Form 10-K, as amended, for the year ended December 31, 2025.