| T. Rowe Price | Baltimore | 1937 |
| Tandem Computers | Cupertino | 1974 |
| TaylorMade Golf Company | Carlsbad | 1979 |
| Tektronix | Beaverton | 1946 |
| Telltale Games | São Rafael | julho 2004 |
| Tenneco | Lake Forest | 1930 |
| Teradyne | North Reading | 1960 |
| Tesla | Austin | 1 de julho de 2003 |
| Texaco | San Ramon | 1901 |
| Texas Instruments | Dallas | 6 de dezembro de 1930 |
| The Babylon Bee | Jupiter | 1 de março de 2016 |
| The Bank of New York Mellon | Nova Iorque | 2007 |
| The Cigna Group | Bloomfield | 1982 |
| The Earth Institute | Nova Iorque | 1995 |
| The Gillette Company | — | 28 de setembro de 1901 |
| The Kennedy/Marshall Company | Santa Mônica | 1992 |
| The Leading Hotels of the World | Nova Iorque | 1928 |
| The McClatchy Company | Sacramento | 1857 |
| The New York Times Company | New York Times Building, Nova Iorque | 18 de setembro de 1851 |
| The NPD Group | Port Washington | 1967 |
| The Onion | Chicago | 1988 |
| The Salt Lake Tribune | — | 1870 |
| The Scotts Miracle-Gro Company | Marysville | 1868 |
| The Spaceship Company | Mojave | 2005 |
| The Travelers Companies | Nova Iorque | 1853 |
| The Trump Organization | Trump Tower | 1923 |
| The Vanguard Group | Malvern | 1 de maio de 1975 |
| The Viper Room | Califórnia | 1993 |
| Thinking Machines Corporation | Carter's Ink Building | 1983 |
| Thinking Machines Lab | — | 2025 |
| Thomas Motor Company | Buffalo | 1902 |
| Thrustmaster | Hillsboro | 1990 |
| TIBCO Software | Palo Alto | 1997 |
| Tiffany & Co. | Nova Iorque | 1837 |
| Tiger Electronics | Vernon Hills | 1978 |
| Timberland | Stratham | 1952 |
| Time Warner Cable | Nova Iorque | 1989 |
| Tommy Hilfiger | Nova Iorque, Amsterdã | 1985 |
| TopCoder | São Francisco | 2001 |
| Tower Records | Sacramento | 1960 |
| Trader Joe's | Monrovia | 1958 |
| Traxxas | McKinney | 1986 |
| Trek Bicycle Corporation | Waterloo | 1976 |
| Trimark Pictures | Santa Mônica | 1985 |
| Trinity Broadcasting Network | Costa Mesa | 1973 |
| Truist Financial | Charlotte | 1872 |
| Trump University | Nova Iorque | 2005 |
| TUMI | Edison | 1975 |