Relationship with BLG and Bayview Financial	6 Months Ended
Jun. 30, 2025
Equity Method Investments and Joint Ventures [Abstract]
Relationship with BLG and Bayview Financial	16. Relationship with BLG and Bayview Financial M&T holds a 20% minority interest in BLG, a privately-held commercial mortgage company. That investment had no remaining carrying value at June 30, 2025 as a result of cumulative losses recognized and cash distributions received in prior years. Cash distributions now received from BLG are recognized as income by M&T and included in Other revenues from operations in the Company's Consolidated Statement of Income. That income totaled $25 million for the six-month period ended June 30, 2024. No distributions were received from BLG for the three-month and six-month periods ended June 30, 2025 or the three-month period ended June 30, 2024. Bayview Financial, a privately-held specialty finance company, is BLG's majority investor. In addition to their common investment in BLG, the Company and Bayview Financial conduct other business activities with each other. The Company has obtained loan servicing rights for mortgage loans from BLG and Bayview Financial having outstanding principal balances of $939 million at June 30, 2025 and $1.0 billion at December 31, 2024. Revenues from those servicing rights were $1 million in each of the three-month periods ended June 30, 2025 and 2024, and $2 million and $3 million in the six-month periods ended June 30, 2025 and 2024, respectively. The Company sub-services residential mortgage loans for Bayview Financial having outstanding principal balances of $157.6 billion and $111.5 billion at June 30, 2025 and December 31, 2024, respectively. Revenues earned for sub-servicing loans for Bayview Financial were $55 million and $31 million for the three-month periods ended June 30, 2025 and 2024, respectively, and $95 million and $63 million for the six-month periods ended June 30, 2025 and 2024, respectively. The Company also held $34 million and $37 million of mortgage-backed securities in its held-to-maturity portfolio at June 30, 2025 and December 31, 2024, respectively, that were securitized by Bayview Financial. The Company had various lending commitments to Bayview Financial totaling $1.0 billion at June 30, 2025, with $666 million and $404 million of outstanding balances at June 30, 2025 and December 31, 2024, respectively. Bayview Financial also maintained $3.5 billion and $2.2 billion of deposit balances at the Company at June 30, 2025 and December 31, 2024, respectively, inclusive of deposits related to loan servicing relationships.

M&T holds a 20% minority interest in BLG, a privately-held commercial mortgage company. That investment had no remaining carrying value at June 30, 2025 as a result of cumulative losses recognized and cash distributions received in prior years. Cash distributions now received from BLG are recognized as income by M&T and included in Other revenues from operations in the Company's Consolidated Statement of Income. That income totaled $25 million for the six-month period ended June 30, 2024. No distributions were received from BLG for the three-month and six-month periods ended June 30, 2025 or the three-month period ended June 30, 2024.

Bayview Financial, a privately-held specialty finance company, is BLG's majority investor. In addition to their common investment in BLG, the Company and Bayview Financial conduct other business activities with each other. The Company has obtained loan servicing rights for mortgage loans from BLG and Bayview Financial having outstanding principal balances of $939 million at June 30, 2025 and $1.0 billion at December 31, 2024. Revenues from those servicing rights were $1 million in each of the three-month periods ended June 30, 2025 and 2024, and $2 million and $3 million in the six-month periods ended June 30, 2025 and 2024, respectively. The Company sub-services residential mortgage loans for Bayview Financial having outstanding principal balances of $157.6 billion and $111.5 billion at June 30, 2025 and December 31, 2024, respectively. Revenues earned for sub-servicing loans for Bayview Financial were $55 million and $31 million for the three-month periods ended June 30, 2025 and 2024, respectively, and $95 million and $63 million for the six-month periods ended June 30, 2025 and 2024, respectively.

The Company also held $34 million and $37 million of mortgage-backed securities in its held-to-maturity portfolio at June 30, 2025 and December 31, 2024, respectively, that were securitized by Bayview Financial. The Company had various lending commitments to Bayview Financial totaling $1.0 billion at June 30, 2025, with $666 million and $404 million of outstanding balances at June 30, 2025 and December 31, 2024, respectively. Bayview Financial also maintained $3.5 billion and $2.2 billion of deposit balances at the Company at June 30, 2025 and December 31, 2024, respectively, inclusive of deposits related to loan servicing relationships.