021000021
View detailsM&T Bank routing number
M&T Bank's primary routing number is 022000046, tied to its roots in Buffalo, New York, where the bank was founded as Manufacturers and Traders Trust Company in 1856. The 0220 prefix reflects the Federal Reserve Bank of New York's Buffalo processing center — a detail that has persisted for over a century as M&T expanded across the Northeast.
Today M&T operates more than 1,000 branches across New York, Maryland, New Jersey, Pennsylvania, Delaware, Connecticut, Vermont, West Virginia, Virginia, and Washington DC. For most customers, 022000046 is the correct routing number, but the bank's acquisition history means some accounts still carry numbers from absorbed institutions.
The People's United acquisition
In April 2022, M&T completed its $7.6 billion acquisition of People's United Bank, a 180-year-old institution headquartered in Bridgeport, Connecticut. The merger added over 400 branches and roughly $63 billion in assets. Most former People's United customers were migrated to M&T systems and received new M&T routing numbers, but migration timelines varied. Some retained their original routing number (221172186) during a transition period. If you were a People's United customer, check your M&T online banking portal to confirm whether your number has been updated to 022000046 or if you're still on the legacy number.
When an acquisition changes your routing number — and when it doesn't
Bank acquisitions don't always trigger immediate routing number changes. When M&T acquired Provident Bank in 2009 and Wilmington Trust in 2011, legacy routing numbers continued to work for years. The acquiring bank typically maintains old numbers in parallel until a full systems conversion forces the cutover. During that window, both numbers may work for incoming transactions, but only one is officially assigned to your account.
The safest practice after any bank merger: log into online banking, confirm the routing number on your account, and update it with employers, billers, and anyone sending you payments. Failing to update can result in delayed or returned ACH transactions once the legacy number is eventually retired.
Wire transfers and international details
For domestic wire transfers, M&T uses the same routing number: 022000046. The SWIFT code for incoming international wires is MANTUS33. M&T charges $30 for outgoing domestic wires and $45 for international, with a cutoff of typically 4:00 PM ET for same-day processing. M&T also supports Zelle for person-to-person payments and offers batch ACH origination for commercial clients, both referencing the same primary routing number.
How Slash eliminates post-merger routing number confusion
Every bank merger creates a period of uncertainty — which routing number is active, whether old numbers still work, when to update payroll and vendor records. Slash sidesteps this entirely with a single, stable account built for businesses. No legacy systems, no migration windows, no guessing. One account with clear routing details, real-time transaction visibility, and financial tools designed for modern operations.
