v3.25.3

Employee Benefits - Schedule of Components of Net Periodic (Benefit) Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
U.K.
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 0	$ 0	$ 0
Interest cost	38	37	114	108
Expected return on plan assets, net of administration expenses	(46)	(48)	(134)	(142)
Amortization of prior-service cost	1	1	2	2
Amortization of net actuarial loss	23	21	67	62
Net periodic cost (benefit)	16	11	49	30
Other
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	10	10	29	29
Expected return on plan assets, net of administration expenses	(13)	(14)	(39)	(41)
Amortization of prior-service cost	0	0	0	0
Amortization of net actuarial loss	4	4	11	10
Net periodic cost (benefit)	1	0	1	(2)
U.S.
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	26	23	77	69
Expected return on plan assets, net of administration expenses	(30)	(33)	(90)	(101)
Amortization of prior-service cost	0	0	0	0
Amortization of net actuarial loss	8	7	26	22
Net periodic cost (benefit)	$ 4	$ (3)	$ 13	$ (10)

Defined Benefit Plan, Net Periodic Benefit Cost Before Recognized Net Gain (Loss) Due to Settlements and Curtailments

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Aon plc 10-Q