| Meade Instruments | Irvine | 1972 |
| Memorex | Cerritos | 1961 |
| Mercer Automobile Company | New Britain | 1909 |
| Meta Platforms | Menlo Park | July 29, 2004 |
| MetLife | New York City | March 24, 1868 |
| Metro Pictures | Los Angeles | 1915 |
| Metro-Goldwyn-Mayer | Los Angeles | April 17, 1924 |
| MFS Investment Management | Boston | 1924 |
| MGM Holdings | Beverly Hills | February 11, 2005 |
| Micro Instrumentation and Telemetry Systems | Albuquerque | 1970 |
| Microchip Technology | Chandler | 1989 |
| Middle-earth Enterprises | Berkeley | 2022 |
| Midway Games | Chicago | 1988 |
| Milton Bradley Company | East Longmeadow | 1860 |
| Moderna | Cambridge | 2010 |
| Mondelez International | Chicago | 2012 |
| Monster Inc. | Brisbane | 1978 |
| Morgan Stanley | New York City | 1931 |
| Morningstar, Inc. | Chicago | 1984 |
| MOS Technology | Norristown | 1969 |
| Motorola Solutions | Chicago | January 4, 2011 |
| MSCI | New York City | 1969 |
| MUFG Union Bank | San Francisco | 1864 |
| México. | Rome, San Clemente | 1999 |
| Narus | Sunnyvale | 1997 |
| National Association of Underwater Instructors | Florida | 1959 |
| National Oilwell Varco | Houston | 1862 |
| National Wrestling Alliance | Houston | 1948 |
| NCR Corporation | Atlanta, Augsburg | 1884 |
| Neiman Marcus | Dallas | 1907 |
| Netflix, Inc. | Los Gatos | August 29, 1997 |
| NetJets | Columbus | 1964 |
| Netlify | San Francisco | January 27, 2014 |
| NetSuite | Austin | 1998 |
| New Balance | Boston | 1906 |
| New York Mercantile Exchange | New York City | 1872 |
| Newegg | City of Industry | 2001 |
| Newmont Mining Corporation | Denver | 1916 |
| News Corp | New York City | June 28, 2013 |
| NexGen | Milpitas | 1986 |
| NeXT | Palo Alto, Redwood City | June 20, 1985 |
| NextEra Energy | Juno Beach | 1925 |
| Nike | Beaverton | January 25, 1964 |
| Noble Energy | Houston | 1932 |
| North American Arms | Provo | 1972 |
| Northwestern Mutual | Milwaukee | 1857 |
| NRG Energy | Princeton, Houston | 1905 |
| NZXT | Los Angeles | 2004 |