| Pitney Bowes | Stamford | 1920 |
| Plantronics | Santa Cruz | 1961 |
| PNC Financial Services | One PNC Plaza | 1982 |
| Powell Peralta | — | 1978 |
| Pratt & Whitney | East Hartford | 1925 |
| Pratt & Whitney Rocketdyne | Canoga Park | 2005 |
| Praxair | Danbury | 1907 |
| Precision Manuals Development Group | Alexandria | 1997 |
| Prince Sports | Bordentown City | 1970 |
| Princess Cruises | Santa Clarita | 1965 |
| Principal Financial Group | Des Moines | 1879 |
| Pro Wrestling Guerrilla | Southern California | 2003 |
| Proactiv Solution | — | 1995 |
| Product Red | New York City | 2006 |
| Progressive Corporation | Mayfield | March 10, 1937 |
| PRS Guitars | Stevensville | 1985 |
| Qlik | King of Prussia | 1993 |
| Quest Software | Aliso Viejo | 1987 |
| Quora | Mountain View | June 21, 2010 |
| QVC | Düsseldorf | 1986 |
| R. J. Reynolds Tobacco Company | Winston-Salem | 1874 |
| Radisson Hotel Group | Minnetonka | 1962 |
| Rainforest Cafe | Houston | 1994 |
| RatPac-Dune Entertainment | Los Angeles | 2006 |
| Razer Inc. | George Town, Singapore, Carlsbad, Irvine, San Francisco | 1998 |
| RCA Corporation | Rockefeller Center, New York City | 1919 |
| RE/MAX | Denver | 1973 |
| RealNetworks | Seattle | 1993 |
| Realty Income Corporation | San Diego | 1969 |
| Red Digital Cinema Camera Company | Lake Forest | 2005 |
| Red Orb Entertainment | Novato | 1997 |
| Red Wing Shoes | Red Wing | 1905 |
| Regeneron Pharmaceuticals | Eastview | 1988 |
| Regent Seven Seas Cruises | Miami | 1990 |
| Regions Financial Corporation | Birmingham | July 13, 1971 |
| Remington Rand | Buffalo, New York City | 1927 |
| Replit | San Francisco | — |
| Revell | Elk Grove Village | 1943 |
| ReverbNation | Durham | October 31, 2006 |
| Ring of Honor | — | 2002 |
| Roblox Corporation | San Mateo | 2004 |
| Rockwell Collins | Cedar Rapids | 1933 |
| Roku, Inc. | Los Gatos | October 2002 |
| Royal Caribbean Group | Miami | 1997 |
| Ryder | Coral Gables | 1933 |
| Sanmina Corporation | San Jose | 1980 |
| Sara Lee Corporation | Downers Grove | 1939 |
| Saucony | Lexington | 1898 |