There are no viable United States banks for everyday banking services in Canada
But Cañada has banks that operate in the states.
Why is that?
Because every single electronic transaction has to be reported to the guvment in Canada, and is constantly monitored, traceable, and seizable. American banks would never agree to that.
https://newcanadianlife.com/which-us-banks-have-branches-in-canada/
Several US banks have operations in Canada. But they offer only wealth management or corporate services. However, if you’re looking for banks with retail services in both countries, you can use Canadian banks such as RBC, BMO, CIBC, Desjardins Bank, National Bank of Canada, TD Bank, and Chase Bank.