| Menominee Area Credit Union | Michigan |
| Menominee County Federal Credit Union | Michigan |
| Meramec Valley Bank | Missouri |
| Mercantil Bank | Florida |
| Mercantile Bank | Illinois |
| Mercantile Bank of Michigan | Michigan |
| Merced Municipal Employees Credit Union | California |
| Merced School Employees Federal Credit Union | California |
| Mercer County Community Federal Credit Union | Pennsylvania |
| Mercer County NJ Teachers Federal Credit Union | New Jersey |
| Mercer County State Bank | Pennsylvania |
| Mercer County WV Teachers Federal Credit Union | West Virginia |
| Mercer Credit Union | Illinois |
| Mercer Savings Bank | Ohio |
| Merchants and Farmers Bank | Arkansas |
| Merchants and Manufacturers Bank | Illinois |
| Merchants and Planters Bank | Mississippi |
| Merchants Bank | Vermont |
| Merchants Bank | Minnesota |
| Merchants Bank | North Dakota |
| Merchants Bank | Alabama |
| Merchants Bank of Alabama | Alabama |
| Merchants Bank of Bangor | Pennsylvania |
| Merchants Bank of California | California |
| Merchants Bank of Indiana | Indiana |
| Merchants & Citizens Bank | Georgia |
| Merchants & Farmers Bank | Mississippi |
| Merchants & Farmers Bank of Greene County | Alabama |
| Merchants & Farmers Bank & Trust Company | Louisiana |
| Merchants & Marine Bank | Mississippi |
| Merchants & Planters Bank | Tennessee |
| Merchants & Planters' Bank | Arkansas |
| Merchants State Bank | South Dakota |
| Merck Employees Federal Credit Union | New Jersey |
| Merck Sharp & Dohme Federal Credit Union | Pennsylvania |
| MERCO Credit Union | California |
| Mercy Credit Union | Missouri |
| Mercy Federal Credit Union | Georgia |
| Mercy Health Partners Federal Credit Union | Ohio |
| Meredith Village Savings Bank | New Hampshire |
| Merho Federal Credit Union | Pennsylvania |
| Meriden Postal Employees Federal Credit Union | Connecticut |
| Meriden Schools Federal Credit Union | Connecticut |
| Meridia Community Federal Credit Union | New York |
| Meridian Bank | Pennsylvania |
| Meridian Credit Union | Iowa |
| Meridian MS Air National Guard Federal Credit Union | Mississippi |
| Meridian Mutual Federal Credit Union | Mississippi |
| Meridian Trust Federal Credit Union | Wyoming |
| Merit Bank | Kansas |
| Meritrust Credit Union | Kansas |
| Meriwest Credit Union | California |
| Merrick Bank | Utah |
| Merrill Federal Savings and Loan Association | Wisconsin |
| Merrimack County Savings Bank | New Hampshire |
| Merrimack Valley Federal Credit Union | Massachusetts |
| Merritt Federal Credit Union | Connecticut |
| Mesquite Credit Union | Texas |
| Messiah Baptist Church Federal Credit Union | New Jersey |
| Messiah Baptist-Jubilee Federal Credit Union | Massachusetts |
| MetaBank | South Dakota |
| Metairie Bank & Trust Company | Louisiana |
| Metco Credit Union | Iowa |
| Methodist Healthcare Federal Credit Union | Tennessee |
| Methodist Hospital Employees Federal Credit Union | Texas |
| Methuen Co-operative Bank | Massachusetts |
| Methuen Municipal Employees Federal Credit Union | Massachusetts |
| Metrex Federal Credit Union | New Jersey |
| Metro Bank | Pennsylvania |
| Metro Bank | Alabama |
| Metro Bank | Kentucky |
| Metro City Bank | Georgia |
| Metro Community Federal Credit Union | West Virginia |
| Metro Credit Union | Missouri |
| Metro Credit Union | Massachusetts |
| Metro Employees Credit Union | Kentucky |
| Metro Federal Credit Union | Illinois |
| Metro Health Services Federal Credit Union | Nebraska |
| Metro Medical Credit Union | Texas |
| Metro North Federal Credit Union | Michigan |
| Metro North Federal Credit Union | Florida |
| Metro Phoenix Bank | Arizona |
| Metropolitan Bank | Mississippi |
| Metropolitan Bank | California |
| Metropolitan Capital Bank & Trust | Illinois |
| Metropolitan Church Federal Credit Union | Virginia |
| Metropolitan Commercial Bank | New York |
| Metropolitan District Employees Credit Union | Connecticut |
| Metropolitan Federal Credit Union | Missouri |
| Metropolitan L Federal Credit Union | Illinois |
| Metropolitan National Bank | Missouri |
| Metropolitan Service Federal Credit Union | Pennsylvania |
| Metropolitan Services Credit Union | Minnesota |
| Metropolitan Teachers Credit Union | Tennessee |
| Metro Shores Credit Union | Michigan |
| Metrowest Community Federal Credit Union | Massachusetts |
| Metro Wire Federal Credit Union | Pennsylvania |
| Metrum Community Credit Union | Colorado |
| Met Tran Federal Credit Union | Texas |
| Metuchen Savings Bank | New Jersey |