| Radford University | public educational institution of the United States, university | — | 1910 |
| Radio Disney | radio network | Dallas | November 28, 1996 |
| Radio Free Asia | radio station, broadcaster, nonprofit organization, news agency | Washington, D.C. | 1994 |
| Radio Free Europe/Radio Liberty | mass media, radio station, news agency, state media | Prague | 1949 |
| Radisson Blu | hotel chain | Brussels metropolitan area | 1994 |
| Ram Trucks | car brand, division, automobile manufacturer | Auburn Hills | 2010 |
| Rankin/Bass Animated Entertainment | television production company | New York City | September 14, 1960 |
| Raven Software | video game developer | Middleton, Madison | 1990 |
| Rawlings | sporting goods manufacturer, business | Town and Country | 1887 |
| RCA Corporation | business | Rockefeller Center, New York City | 1919 |
| RCA Records | record label, record company, business | New York City | 1901 |
| Real3D | business | Orlando | 1986 |
| RealNetworks | privately held company, business, enterprise | Seattle | 1993 |
| Red Storm Entertainment | video game developer | Cary | 1996 |
| Reddit | user-generated content platform, art-sharing website, news aggregation website, social networking service, aggregator, social news website, online community | San Francisco | June 23, 2005 |
| Redfin | real estate company, business, online real estate database | Seattle | 2004 |
| Reed College | liberal arts college, Colleges That Change Lives, private not-for-profit educational institution | — | 1908 |
| Regent Seven Seas Cruises | business | Miami | 1990 |
| Relativity Media | film production company, film distributor | Beverly Hills | 2004 |
| Remo | business, musical instrument manufacturing company, enterprise | Santa Clarita | 1957 |
| Remote Control Productions | music publisher, business, enterprise | Santa Monica | 1989 |
| Renaissance Hotels | hotel | — | 1982 |
| REO Motor Car Company | business, automobile manufacturer | Lansing | 1905 |
| Replit | business, online integrated development environment | San Francisco | — |
| Republic Airways | regional airline | Indianapolis | 1998 |
| Republic Pictures | Poverty Row | Hollywood | 1935 |
| Retro Studios | video game developer | Austin | October 1998 |
| ReverbNation | website, business | Durham | October 31, 2006 |
| Revlon | business, enterprise, public company | New York City | 1932 |
| Reynolds American | business, enterprise, public company | Winston-Salem | 2004 |
| Rhino Entertainment Company | production company, record company, subsidiary company | Los Angeles | 1998 |
| Rhythm and Hues Studios | film studio | El Segundo | 1987 |
| Rice University | research university, private not-for-profit educational institution, private university | Houston | 1891 |
| Richard Childress Racing | auto racing team, business | — | 1969 |
| Ring Ka King | business | Pune | 2011 |
| Ring of Honor | business, enterprise, professional wrestling promotion | — | 2002 |
| Ripple Effect Studios | video game developer | Los Angeles | 2013 |
| Rivian Automotive | business, enterprise, automobile manufacturer, public company | Detroit | June 2009 |
| RJR Nabisco | business | Cobb County, Winston-Salem, New York City | April 25, 1986 |
| RKO Pictures | film production company, film distributor, business | Manhattan | October 23, 1928 |
| Robinhood | brokerage firm, business, public company | Palo Alto | 2013 |
| Robinson Helicopter Company | business, enterprise | Zamperini Field | 1973 |
| Rochester Institute of Technology | university of technology, research university, engineering school, space grant institution, private not-for-profit educational institution, open-access publisher, private university | — | June 12, 1829 |
| Rockstar New England | video game developer | Andover | 1999 |
| Rockwell Collins | defense contractor, business, public company, aerospace manufacturer | Cedar Rapids | 1933 |
| Rogue | film production company | Universal City | 1997 |
| Room to Read | nonprofit organization, business | San Francisco | 2000 |
| Rooster Teeth | YouTube channel, film production company | Austin, Los Angeles, Flower Mound | April 1, 2003 |
| Rough Draft Studios | business, enterprise | Glendale | 1990 |
| Rowman & Littlefield | book publisher, publishing house | Lanham | 1949 |
| Roxy Theatre | nightclub, music venue | — | September 23, 1973 |
| Royal Caribbean Group | business, enterprise, public company | Miami | 1997 |
| Royal Caribbean International | cruise line | Miami | 1968 |
| RSA | business, enterprise | Bedford | 1986 |
| RTX | defense contractor, business, public company | Arlington County | April 3, 2020 |
| Running with Scissors | video game developer | Tucson | 1996 |
| Rutgers University Press | university press | New Brunswick | 1936 |
| Rutherford B. Hayes Presidential Center | library | — | 1912 |
| Ryan Aeronautical | business | San Diego | 1934 |
| Ryder | business, retail chain, public company | Coral Gables | 1933 |