v3.25.4

Segment Information (Tables)

12 Months Ended

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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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.

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