| Karnival of the Arts | Kempton | PA | United States | September | Labor Day Weekend | 5 Days | Variety | Music |
| Kauai Folk Festival | Lihue, Kauai | HI | United States | October | 1st Weekend | 2 Days | Singer-songwriter, Americana, folk | Music |
| Kent American Roots Music Festival | Kent | OH | United States | April | 4th Weekend | 1 Day | Americana, with strong representation of folk, roots, and bluegrass influences. Features singer-songwriter artists alongside bands. | Music |
| Kerrville Folk Festival | Kerrville | TX | United States | October | 2nd Weekend | 3 Days | Folk, with strong representation of Americana, singer-songwriter, and roots music. Features a unique format with multiple stages and extended duration, offering a wide range of artists. | Music |
| Key West Songwriter Festival | Key West | FL | United States | May | 1st Weekend | 5 Days | Singer-songwriter, Americana, folk | Music |
| Keystone Bluegrass and Beer Festival | Keystone | CO | United States | August | 1st Weekend | 2 Days | Bluegrass, with potential inclusion of Americana and roots influences. | Music |
| Kickn’ Up Kountry | Karlstad | MN | United States | June | 2nd Weekend | 4 Days | Country | Music |
| Kilgore Station Bluegrass Festival | Cross Plains | TN | United States | June | 3rd Weekend | 2 Days | Bluegrass | Music |
