| Parallels | Renton | 1999 |
| Paramount Animation | Los Angeles | 2011 |
| Paramount Global | Nova Iorque, One Astor Plaza | 4 de dezembro de 2019 |
| Paramount Global Content Distribution | Santa Mônica, Nova Iorque | 1962 |
| Parker Pen Company | Newhaven, Londres | 1888 |
| Parkwood Entertainment | Los Angeles | 2008 |
| Patagonia (marca de roupa) | Ventura | 1973 |
| Peavey | Meridian | 1965 |
| Peerless | Cleveland | 1900 |
| Peet's Coffee | Emeryville | 1966 |
| Penguin Random House | Nova Iorque | 1 de julho de 2013 |
| Pennsylvania Railroad | Filadélfia | 13 de abril de 1846 |
| Pennzoil | Houston | 1963 |
| Pentaho | Orlando | 2004 |
| PeopleSoft | Pleasanton, Califórnia | 1987 |
| PerkinElmer | Waltham | 1937 |
| Perplexity.ai | São Francisco | 7 de dezembro de 2022 |
| Philip Morris International | Stamford, Lausana | 1987 |
| Phillips 66 | Westchase | 1 de maio de 2012 |
| Phillips Petroleum | Bartlesville | 1917 |
| Pierce-Arrow | Buffalo | 1870 |
| Pilgrim's Pride | Greeley | 1946 |
| PIMCO | Newport Beach | 1971 |
| Pinkberry | Los Angeles | 2005 |
| Pinnacle Systems | Mountain View | 1986 |
| Pitney Bowes | Stamford | 1920 |
| Plaxo | Sunnyvale | julho 2001 |
| PNC Financial Services | One PNC Plaza | 1982 |
| Polycom | São José | 1990 |
| PR Newswire | Manhattan | 8 de março de 1954 |
| Precision Manuals Development Group | Alexandria | 1997 |
| Prince Sports | Bordentown | 1970 |
| Princess Cruises | Santa Clarita | 1965 |
| Proactiv Solution | — | 1995 |
| Procter & Gamble | Ohio, Cincinnati | 31 de outubro de 1837 |
| Product Red | Nova Iorque | 2006 |
| Progressive Corporation | Mayfield | 10 de março de 1937 |
| Providence Equity Partners | 50 Kennedy Plaza | 1989 |
| PRS Guitars | Stevensville | 1985 |
| Pyra Labs | São Francisco | 1999 |
| Qorvo | Greensboro | 2015 |
| Qualcomm | San Diego | julho 1985 |
| Qualtrics | Provo | 2002 |
| Quest Software | Aliso Viejo | 1987 |
| Quiksilver | Huntington Beach | 1969 |
| R. J. Reynolds Tobacco Company | Winston-Salem | 1874 |
| Radisson Hotel Group | Minnetonka | 1962 |
| Rainforest Cafe | Houston | 1994 |