Borrowings (Tables)

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

Amounts and Interest Rates of Short-term Borrowings

The amounts and interest rates of short-term borrowings were as follows:

(Dollars in millions)	Repurchase Agreements			FHLB Advances			Total
At December 31, 2023
Amount outstanding	$	316		$	5,000		$	5,316
Weighted-average interest rate		3.26	%		5.35	%		5.23	%
At December 31, 2022
Amount outstanding	$	355		$	3,200		$	3,555
Weighted-average interest rate		1.01	%		4.59	%		4.24	%

Long-term Borrowings

Long-term borrowings were as follows:

	December 31,
(Dollars in millions)	2023		2022
Senior notes of M&T:
Variable rate due 2023	$	—	$	250
3.55% due 2023		—		494
4.55% fixed/variable due 2028		484		477
7.41% fixed/variable due 2029		1,028		—
5.05% fixed/variable due 2034		970		—
Senior notes of M&T Bank:
2.90% due 2025		750		750
5.40% due 2025		499		499
4.65% due 2026		1,296		—
4.70% due 2028		1,196		—
Subordinated notes of M&T:
5.75% due 2024		76		77
Subordinated notes of M&T Bank:
4.00% due 2024		401		404
3.40% due 2027		472		463
Junior subordinated debentures of M&T associated with    preferred capital securities:
Fixed rates:
BSB Capital Trust I — 8.125%, due 2028		16		16
Provident Trust I — 8.29%, due 2028		32		31
Southern Financial Statutory Trust I — 10.60%, due 2030		7		7
Variable rates:
First Maryland Capital I — due 2027		150		150
First Maryland Capital II — due 2027		153		152
Allfirst Asset Trust — due 2029		98		97
BSB Capital Trust III — due 2033		15		15
Provident Statutory Trust III — due 2033		60		59
Southern Financial Capital Trust III — due 2033		9		9
Asset-backed notes		474		—
Other		15		15
	$	8,201	$	3,965

Maturity of Long-term Borrowings

Long-term borrowings at December 31, 2023 mature as follows:

(Dollars in millions)
Year ending December 31:
2024	$	527
2025		1,251
2026		1,297
2027		775
2028		1,728
Later years		2,623
	$	8,201