v3.25.4

Segment Information (Tables) | 12 Months Ended
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Dec. 31, 2025
Segment Reporting [Abstract] |
Schedule of Selected Information and Details for MMC's Operating Segments | Selected information about the Company’s segments and geographic areas of operation are as follows:
For the Years Ended December 31, (In millions) |  | Revenue |  | Compensation and benefits |  | Depreciation and amortization expense |  | Identified intangible amortization expense |  | Other segment items | Operating Income (Loss)
2025 – |  |  |  |  |  |  |  |  |  |  |
Risk and Insurance Services |  | $ | 17,265 |  | (a) | $ | 9,711 |  |  | $ | 204 |  |  | $ | 475 |  |  | $ | 2,239 |  | $ | 4,636 |
Consulting |  | 9,794 |  | (b) | 5,710 |  |  | 100 |  |  | 74 |  |  | 2,014 |  | 1,896 |
Total Segments |  | 27,059 |  |  | 15,421 |  |  | 304 |  |  | 549 |  |  | 4,253 |  | 6,532 |
Corporate/Eliminations |  | (78) |  |  | 156 |  |  | 57 |  |  | — |  |  | 18 |  | (309) |
Total Consolidated |  | $ | 26,981 |  |  | $ | 15,577 |  |  | $ | 361 |  |  | $ | 549 |  |  | $ | 4,271 |  | $ | 6,223 |
2024 – |  |  |  |  |  |  |  |  |  |  |
Risk and Insurance Services |  | $ | 15,395 |  | (a) | $ | 8,499 |  |  | $ | 192 |  |  | $ | 326 |  |  | $ | 2,013 |  | $ | 4,365 |
Consulting |  | 9,133 |  | (b) | 5,358 |  |  | 114 |  |  | 51 |  |  | 1,840 |  | 1,770 |
Total Segments |  | 24,528 |  |  | 13,857 |  |  | 306 |  |  | 377 |  |  | 3,853 |  | 6,135 |
Corporate/Eliminations |  | (70) |  |  | 139 |  |  | 63 |  |  | — |  |  | 46 |  | (318) |
Total Consolidated |  | $ | 24,458 |  |  | $ | 13,996 |  |  | $ | 369 |  |  | $ | 377 |  |  | $ | 3,899 |  | $ | 5,817 |
2023 – |  |  |  |  |  |  |  |  |  |  |
Risk and Insurance Services |  | $ | 14,089 |  | (a) | $ | 7,702 |  |  | $ | 190 |  |  | $ | 297 |  |  | $ | 1,955 |  | $ | 3,945 |
Consulting |  | 8,709 |  |  | 5,249 |  |  | 106 |  |  | 46 |  |  | 1,642 |  | 1,666 |
Total Segments |  | 22,798 |  |  | 12,951 |  |  | 296 |  |  | 343 |  |  | 3,597 |  | 5,611 |
Corporate/Eliminations |  | (62) |  |  | 148 |  |  | 74 |  |  | — |  |  | 45 |  | (329) |
Total Consolidated |  | $ | 22,736 |  |  | $ | 13,099 |  |  | $ | 370 |  |  | $ | 343 |  |  | $ | 3,642 |  | $ | 5,282 |
(a)Includes interest income on fiduciary funds of $403 million, $497 million and $453 million in 2025, 2024 and 2023, respectively, and equity method income of $24 million, $22 million and $18 million in 2025, 2024 and 2023, respectively. Revenue in 2025 also includes $28 million from a gain on the sale of the TCAS business and a gain on remeasurement of a previously held equity method investment to fair value upon consolidation. Revenue in 2023 includes a gain from a legal settlement with a competitor of $58 million, excluding legal fees. (b)Includes inter-segment revenue of $73 million, $60 million and $56 million in 2025, 2024 and 2023, respectively. Revenue in 2024 includes a net gain of $35 million on the sale of the Mercer U.K. pension administration and U.S. health and benefits administration business. Revenue in 2024 also includes a gain of $20 million from the sale of a business in Marsh Management Consulting.
Schedule of Details of Operating Segment Revenue | Details of operating segment revenue are as follows:
For the Years Ended December 31,
(In millions) |  | 2025 |  | 2024 |  | 2023
Risk and Insurance Services |  |  |  |  |  |
Marsh Risk |  | $ | 14,630 |  |  | $ | 12,851 |  |  | $ | 11,657 |
Guy Carpenter |  | 2,635 |  |  | 2,544 |  |  | 2,432 |
Total Risk and Insurance Services |  | 17,265 |  |  | 15,395 |  |  | 14,089 |
Consulting |  |  |  |  |  |
Mercer |  | 6,190 |  |  | 5,743 |  |  | 5,587 |
Marsh Management Consulting |  | 3,604 |  |  | 3,390 |  |  | 3,122 |
Total Consulting |  | 9,794 |  |  | 9,133 |  |  | 8,709 |
Total Segments |  | 27,059 |  |  | 24,528 |  |  | 22,798 |
Corporate/Eliminations |  | (78) |  |  | (70) |  |  | (62) |
Total |  | $ | 26,981 |  |  | $ | 24,458 |  |  | $ | 22,736 |
Schedule of Information by Geographic Area | Information by geographic area is as follows:
For the Years Ended December 31,
(In millions) |  | 2025 |  | 2024 |  | 2023
Revenue |  |  |  |  |  |
United States (a) |  | $ | 13,344 |  |  | $ | 11,671 |  |  | $ | 10,924 |
United Kingdom (b) |  | 3,816 |  |  | 3,595 |  |  | 3,555 |
Other (c) |  | 9,899 |  |  | 9,262 |  |  | 8,319 |
|  | 27,059 |  |  | 24,528 |  |  | 22,798 |
Corporate/Eliminations |  | (78) |  |  | (70) |  |  | (62) |
Total |  | $ | 26,981 |  |  | $ | 24,458 |  |  | $ | 22,736 |
(a)Revenue in 2025 includes a gain on the sale of the TCAS business of $15 million. Revenue in 2024 includes the loss on the sale of the Mercer U.S. health and benefits administration business of $35 million, and a gain of $20 million from the sale of a business in Marsh Management Consulting. (b)Revenue in 2024 includes the gain on the sale of the Mercer U.K. pension administration business of $70 million. Revenue in 2023 includes a gain from a legal settlement with a competitor of $58 million, excluding legal fees. (c)Revenue in 2025 incudes a $13 million gain on remeasurement of a previously held equity method investment to fair value upon consolidation.
For the Years Ended December 31,
(In millions) |  | 2025 |  | 2024 |  | 2023
Fixed Assets, Net |  |  |  |  |  |
United States |  | $ | 469 |  |  | $ | 494 |  |  | $ | 468 |
United Kingdom |  | 136 |  |  | 150 |  |  | 168 |
Other |  | 224 |  |  | 215 |  |  | 246 |
Total |  | $ | 829 |  |  | $ | 859 |  |  | $ | 882 |

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- Definition Tabular disclosure of information concerning material long-lived assets (excluding financial instruments, customer relationships with financial institutions, mortgage and other servicing rights, deferred policy acquisition costs, and deferred taxes assets) located in identified geographic areas and/or the amount of revenue from external customers attributed to that country from which revenue is material. An entity may also provide subtotals of geographic information about groups of countries. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 41 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-41 + Details
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- Definition Tabular disclosure of the profit or loss and total assets for each reportable segment. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 25 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-25 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-22 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 30 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-30 + Details
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