| Seabourn Cruise Line | Seattle, Miami | 1986 |
| Seagate | Cupertino | 1979 |
| Sealy Corporation | Trinity | 1881 |
| Sears | Hoffman Estates | 1892 |
| Sears Holdings Corporation | Hoffman Estates | 2005 |
| Seattle's Best Coffee | Seattle | 1991 |
| Seeburg Corporation | Chicago | 1902 |
| Semiconductor Cypress | San José | 1982 |
| Seymour Duncan | Goleta | 1978 |
| Shaba Games | San Francisco | 1997 |
| Shen Yun | Deerpark | 2006 |
| Sheraton Hotels & Resorts | White Plains | 1937 |
| Shimmer Women Athletes | Illinois, Chicago, Berwyn | 6 de noviembre de 2005 |
| Shure Incorporated | Niles | 1925 |
| Siebel Systems | Austin | 1993 |
| Silver Lake | Menlo Park | 1999 |
| Similarweb | Guivatayim | 2007 |
| Sinclair Broadcast Group | Hunt Valley, Cockeysville, Union Valley | 1971 |
| SiRF | San José | 1995 |
| Sirius XM Radio | Nueva York | 29 de julio de 2008 |
| Six Flags | Arlington | 1961 |
| Skullcandy | Park City | 2003 |
| Skywalker Sound | Lucas Valley | 1975 |
| Slack Technologies | San Francisco | 2009 |
| Smith & Wesson | Springfield | 1852 |
| Snap-on | Kenosha | 1920 |
| Snowflake Inc. | San Mateo | 2012 |
| Sociedad para la creación de idiomas | Garden Grove | 2007 |
| Southern Company | Atlanta | 1945 |
| Soylent | Los Ángeles | 2013 |
| SpaceX | Starbase | 14 de marzo de 2002 |
| SpaceXAI | Área de la Bahía de San Francisco | 9 de marzo de 2023 |
| Spanx | Atlanta | 2000 |
| Speedway Motorsports | Concord | 1959 |
| Sports Reference | Filadelfia | 3 de diciembre de 2007 |
| Springfield Armory | Geneseo | 1974 |
| Sprouts | Phoenix | julio 2002 |
| Stage 6 Films | Culver City | 2007 |
| Standard Oil | Ohio, Cleveland, Nueva York | 1890 |
| Standard Oil of Ohio | Cleveland | 1911 |
| Starkey Hearing Technologies | Eden Prairie | 1967 |
| Starwood Hotels & Resorts Worldwide | White Plains | 1930 |
| Starz Entertainment | Santa Mónica | 28 de abril de 1997 |
| State Street Corporation | Boston | 1792 |
| Steak 'n Shake | Indianápolis | 1934 |
| Steelcase | Grand Rapids | 1912 |
| Stinson | Dayton | 1920 |
| Stratfor | Austin | 1996 |