CONSOLIDATED STATEMENT OF INCOME (UNAUDITED) - USD ($) shares in Millions, $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Revenues [Abstract]
Interest income	[1]	$ 36,690	$ 36,456	$ 106,215	$ 108,666
Interest expense	[1]	21,750	23,094	62,088	68,304
Net interest income	[1]	14,940	13,362	44,127	40,362
Commissions and fees	[1]	2,888	2,589	8,340	7,780
Principal transactions	[2]	2,772	2,835	8,785	8,656
Administration and other fiduciary fees		1,117	1,059	3,285	3,142
Realized gains on sales of investments, net		105	72	364	210
Net impairment losses on investments recognized in earnings		(25)	(41)	(118)	(92)
Other revenue	[2]	293	333	571	1,199
Total non-interest revenues		7,150	6,847	21,227	20,895
Total revenues, net of interest expense	[1]	22,090	20,209	65,354	61,257
Provisions for credit losses and for benefits and claims
Provision for credit losses on loans		2,259	2,382	7,297	7,163
Provision (release) for credit losses on HTM debt securities		(5)	50	(3)	55
Provision for credit losses on other assets		79	110	499	226
Policyholder benefits and claims		17	28	63	73
Provision (release) for credit losses on unfunded lending commitments		100	105	189	(1)
Total provisions for credit losses and for benefits and claims		2,450	2,675	8,045	7,516
Operating expenses
Compensation and benefits	[1]	7,474	7,058	22,571	21,619
Technology/communication	[1]	2,325	2,273	6,994	6,757
Transactional and product servicing(3)	[1],[3]	1,110	1,103	3,396	3,336
Premises and equipment	[1]	607	606	1,796	1,788
Professional services	[1]	514	491	1,500	1,366
Advertising and marketing	[1]	260	282	779	790
Restructuring	[1]	(5)	9	(10)	270
Other operating(1)(3)	[1],[3]	2,005	1,322	4,266	4,571
Total operating expenses	[1]	14,290	13,144	41,292	40,497
Income from continuing operations before income taxes		5,350	4,390	16,017	13,244
Provision for income taxes		1,559	1,116	4,085	3,299
Income from continuing operations		3,791	3,274	11,932	9,945
Discontinued operations
Income (loss) from discontinued operations		(1)	(1)	(2)	(2)
Benefit for income taxes		0	0	0	0
Income (loss) from discontinued operations, net of taxes		(1)	(1)	(2)	(2)
Net income before attribution to noncontrolling interests		3,790	3,273	11,930	9,943
Noncontrolling interests		38	35	95	117
Citigroup’s net income		$ 3,752	$ 3,238	$ 11,835	$ 9,826
Basic earnings per share
Income from continuing operations (in dollars per share)	[4]	$ 1.89	$ 1.53	$ 5.87	$ 4.67
Income from discontinued operations, net of taxes (in dollars per share)	[4]	0	0	0	0
Net income (in dollars per share)	[4]	$ 1.89	$ 1.53	$ 5.87	$ 4.67
Weighted-average common shares outstanding (in shares)		1,820.3	1,899.9	1,851.7	1,906.0
Diluted earnings per share
Income from continuing operations (in dollars per share)	[4]	$ 1.86	$ 1.51	$ 5.78	$ 4.61
Income (loss) from discontinued operations, net of taxes (in dollars per share)	[4]	0	0	0	0
Net income (in dollars per share)	[4]	$ 1.86	$ 1.51	$ 5.78	$ 4.61
Adjusted weighted-average diluted common shares outstanding (in shares)		1,862.6	1,940.3	1,891.8	1,943.1

[1] Effective January 1, 2025, certain transaction processing fees paid by Citi, primarily to credit card networks, which were previously presented within Other operating expenses, are presented as contra-revenue within Commissions and fees reported in Non-interest revenue. Prior periods were conformed to reflect this change in presentation.

[2] Effective July 1, 2025, gains and losses on certain economic and qualifying hedging derivatives and foreign currency transaction gains and losses related to non-U.S. dollar debt and certain foreign operations in countries with highly inflationary economies with the U.S. dollar as their functional currency, which were previously presented within Other revenue, are presented within Principal transactions. Prior periods were conformed to reflect this change in presentation.

[3] Effective July 1, 2025, certain expenses incurred in ongoing support of products and services that are predominantly variable costs, which were previously presented within Other operating expenses and Transactional and tax charges, are aggregated and presented within a new expenses category, Transactional and product servicing (see “Glossary” below for definition). Moreover, certain non-income tax charges incurred, which were previously presented within Transactional and tax charges and do not align with the redefined Transactional and product servicing, are presented within Other operating. Prior periods were conformed to reflect this change in presentation.

[4] Due to rounding, earnings per share on continuing operations and discontinued operations may not sum to earnings per share on net income.