| J. B. Hunt | business, public company | Lowell | 1961 |
| J. C. Penney | department store chain, organization, business, public company | Plano | 1902 |
| Jack Daniel's | distillery, business, enterprise | Jack Daniel's Distillery | 1866 |
| Jack in the Box | fast food restaurant chain, public company | San Diego | 1951 |
| Jackson Guitars | business, musical instrument manufacturing company | Scottsdale | 1980 |
| Jacksonville University | private not-for-profit educational institution, university | Palm Beach Gardens | 1934 |
| Jakks Pacific | business, public company | Malibu | 1995 |
| Jamba | restaurant chain, business, public company | Frisco | 1990 |
| James Madison University | public educational institution of the United States, public university | Harrisonburg | 1908 |
| Janet | airline | Las Vegas | 1972 |
| Jeppesen | business | Inverness | 1934 |
| Jerry Bruckheimer Films | film production company, independent business | Santa Monica | 1990 |
| Jet | brand, business, gas station chain | — | — |
| Jewish Theological Seminary of America | Jewish seminary, private not-for-profit educational institution | New York City | 1886 |
| Jewish Virtual Library | virtual library, online encyclopedia | — | 1998 |
| Jim Crockett Promotions | business | Charlotte | 1931 |
| John Carroll University | Jesuit university, private not-for-profit educational institution | — | 1886 |
| John F. Kennedy Presidential Library and Museum | museum, library | — | 1979 |
| John F. Kennedy School of Government | public policy school, graduate school, private school | Cambridge | 1936 |
| John Hancock Insurance | business | Boston | 1862 |
| Johnny Rockets | fast food restaurant chain, restaurant chain | Lake Forest | 1986 |
| Johns Hopkins University | private not-for-profit educational institution, research institute, open-access publisher, private university | Baltimore | 1876 |
| Johns Hopkins University Press | book publisher, publishing house, university press | Baltimore | 1878 |
| Johnson & Johnson | pharmaceutical company, organization, business, medical device company, enterprise, public company | New Brunswick | 1886 |
| Johnson & Wales University, Providence | university | — | 1914 |
| Jones Day | law firm | Washington, D.C. | 1893 |
| Jones Lang LaSalle | business, enterprise, public company | Chicago, Aon Center | 1783 |
| Juilliard School | conservatory, drama school, private not-for-profit educational institution | New York City | 1905 |
| Juniper Networks | business, enterprise, public company | Sunnyvale | February 6, 1996 |
| Juul | business | San Francisco | July 2017 |