Commitments and Contingent Liabilities (Tables)

9 Months Ended

Sep. 30, 2025

Commitments and Contingencies Disclosure [Abstract]

Schedule of Fair Value, Off-balance Sheet Risks

The following table provides details of Northern Trust's off-balance sheet financial instruments as of September 30, 2025 and December 31, 2024.

TABLE 70: SUMMARY OF OFF-BALANCE SHEET FINANCIAL INSTRUMENTS

	SEPTEMBER 30, 2025						DECEMBER 31, 2024
(In Millions)	ONE YEAR AND LESS		OVER ONE YEAR		TOTAL		ONE YEAR AND LESS		OVER ONE YEAR		TOTAL
Undrawn Commitments(1)	$	10,276.9	$	17,504.9	$	27,781.8	$	10,849.6	$	17,293.2	$	28,142.8
Standby Letters of Credit and Financial Guarantees(2)(3)	125,473.6		333.2		125,806.8		112,256.3		490.1		112,746.4
Commercial Letters of Credit	37.3		0.2		37.5		20.3		0.2		20.5
Securities Lent with Indemnification	167,606.5		—		167,606.5		144,543.7		—		144,543.7
Total Off-Balance Sheet Financial Instruments	$	303,394.3	$	17,838.3	$	321,232.6	$	267,669.9	$	17,783.5	$	285,453.4

(1) These amounts exclude $221.1 million and $268.5 million of commitments participated to others at September 30, 2025 and December 31, 2024, respectively.

(2) These amounts include $69.1 million and $109.4 million of standby letters of credit secured by cash deposits or participated to others as of September 30, 2025 and December 31, 2024, respectively.

(3) These amounts include a $124.0 billion and $110.8 billion guarantee to the FICC under the sponsored member program, without taking into consideration the related collateral, as of September 30, 2025 and December 31, 2024, respectively.