| Miami FC | USL Championship | Miami | 2015 | Pitbull Stadium |
| Miami Fusion FC | National Premier Soccer League | — | 2014 | — |
| Miami Toros | North American Soccer League | Washington, D.C. | 1972 | Miami Orange Bowl |
| Michigan Stars FC | National Independent Soccer Association | Detroit | 1982 | Wisner Stadium |
| Milwaukee Rampage | A-League | Milwaukee | 1993 | Uihlein Soccer Park |
| Milwaukee Torrent | National Premier Soccer League | Milwaukee | January 2015 | — |
| Milwaukee Wave | Major Indoor Soccer League | — | 1984 | UW–Milwaukee Panther Arena |
| Minneapolis City SC | National Premier Soccer League | Minneapolis | 2015 | — |
| Minnesota Kings | National Premier Soccer League | — | 2009 | — |
| Minnesota Strikers | North American Soccer League | Minneapolis | 1984 | Hubert H. Humphrey Metrodome |
| Minnesota Thunder | USL First Division, A-League | Blaine | 1990 | National Sports Center |
| Minnesota Twin Stars | National Premier Soccer League | — | 1997 | Minnetonka High School |
| Minnesota United FC | Major League Soccer | Minneapolis | 2015 | Allianz Field |
| Minnesota United FC | North American Soccer League | — | 2010 | National Sports Center |
| Mississippi Beach Kings | Eastern Indoor Soccer League | — | 1998 | Mississippi Coast Coliseum |
| Mississippi Brilla | USL League Two | Clinton | 2006 | — |
| Mississippi Storm | National Premier Soccer League | — | 2011 | — |
| Missouri Comets | Major Indoor Soccer League | — | 2010 | Independence Events Center |
| Monterey Blues | Women's Premier Soccer League | — | 2007 | Monterey Peninsula College |
| Montgomery United FC | USL League Two | Montgomery | 2024 | — |
| Montreal Manic | North American Soccer League | Montreal | 1981 | Olympic Stadium |
| Moreno Valley FC | United Premier Soccer League | — | 2015 | — |
| Morris County Colonials | National Premier Soccer League | — | 2007 | — |
| Motagua New Orleans | — | New Orleans | 1984 | Pan American Stadium |
| MP United F.C. | M*League Division 1 | Northern Mariana Islands | 2008 | — |
| Myrtle Beach FC | National Premier Soccer League | Myrtle Beach | 2011 | Doug Shaw Memorial Stadium |
| Nashville Diamonds | American Soccer League | Nashville | 1982 | — |
| Nashville FC | National Premier Soccer League | — | 2013 | FirstBank Stadium |
| Nashville Metros | A-League, USL League Two | Nashville | 1989 | E. S. Rose Park |
| Nashville SC | Major League Soccer | Nashville | 2017 | Nissan Stadium, Geodis Park |
| Nashville SC | USL Championship | Nashville | May 19, 2016 | First Horizon Park |
| Nashville SC U23 | USL League Two | — | 2016 | FirstBank Stadium |
| Nevada Wonders | USL League Two | — | 2003 | Carson High School |
| New Bedford Whalers | Southern New England Soccer League | New Bedford | 1921 | — |
| New England Futbol Club | — | Greater Boston | 2009 | — |
| New England Revolution | Major League Soccer | — | — | Gillette Stadium |
| New England Revolution | Major League Soccer | Foxborough | 1995 | Gillette Stadium |
| New England Sharks | — | New Bedford | 1981 | — |
| New England Tea Men | North American Soccer League | Foxborough | 1978 | Foxboro Stadium |
| New Hampshire Mountaineers | National Premier Soccer League | — | 2009 | — |
| New Jersey Americans | — | New Brunswick | 1976 | — |
| New Jersey Blaze | National Premier Soccer League | — | 2009 | Rowland Park |
| New Jersey Brewers | — | New Jersey | 1972 | — |
| New Jersey Gladiators SC | American Soccer League | — | 2012 | Pascack Valley High School |
| New Jersey Stallions | USL League Two | — | 1996 | DePaul Catholic High School |
| New Mexico Chiles | United Soccer League | Albuquerque | 1990 | — |
| New Mexico United | USL Championship | Albuquerque | June 6, 2018 | Isotopes Park |
| New Orleans Jesters | National Premier Soccer League | New Orleans | 2003 | Pan American Stadium |