| National Association for Stock Car Auto Racing | Charlotte | 1948 |
| National Oilwell Varco | Houston | 1862 |
| National Semiconductor | Santa Clara | 1959 |
| National Wrestling Alliance | Houston | 1948 |
| Navteq | Chicago | 1985 |
| Neiman Marcus | Dallas | 1907 |
| Neon | Nova Iorque | 2017 |
| NetJets | Columbus | 1964 |
| New Holland | Itália | 1891 |
| New York Life Insurance Company | Nova Iorque | 1845 |
| New York Mercantile Exchange | Nova Iorque | 1872 |
| New York Shipbuilding Corporation | Camden | 1899 |
| Newmont Mining Corporation | Denver | 1916 |
| News Corp | Nova Iorque | 28 de junho de 2013 |
| NexGen | Milpitas | 1986 |
| NeXT | Palo Alto, Redwood City | 20 de junho de 1985 |
| Nik Software | San Diego | 1995 |
| Nike | Beaverton | 25 de janeiro de 1964 |
| Noble Energy | Houston | 1932 |
| Nomura Securities Co Ltd | Nihonbashi, Tóquio | 7 de maio de 2001 |
| Norfolk Southern | Norfolk | 1894 |
| North American Arms | Provo | 1972 |
| Northern Trust | Illinois, Chicago | 1889 |
| Norwegian Cruise Line | Condado de Miami-Dade | 1966 |
| NRG Energy | Princeton, Houston | 1905 |
| NullSoft | Phoenix | 1997 |
| Nvidia | Santa Clara | 5 de abril de 1993 |
| Oakley, Inc. | Foothill Ranch | 1975 |
| Ocean Spray | Lakeville | 1930 |
| OceanGate | Everett | 2009 |
| OfficeMax | — | 1988 |
| Ohio Valley Wrestling | Louisville | 1997 |
| Onsemi | Scottsdale | 18 de junho de 1992 |
| OpenDNS | São Francisco | julho 2006 |
| OpenTable | São Francisco | 1998 |
| OQO | São Francisco | 2000 |
| Oracle Corporation | Austin | 16 de junho de 1977 |
| Organon & Co. | Oss | 1923 |
| Oscar Mayer | Chicago | 1883 |
| Oshkosh Corporation | Oshkosh | 1917 |
| Otis Elevator Company | Farmington | 1853 |
| Overbrook Entertainment | Beverly Hills, Los Angeles | 1998 |
| Owens Corning | Toledo | 1938 |
| Packard Bell | Chatsworth | 1926 |
| Padlet | São Francisco | 1 de dezembro de 2012 |
| Pan American World Airways | Nova Iorque | 14 de março de 1927 |
| Panic Inc. | Portland, Oregon | — |
| Pantene | Suíça | 1945 |