| Ladies of Bluegrass Music Festival | Green Bay | WI | United States | April | 3rd Weekend | 1 Day | Bluegrass | Music |
| Lake Cumberland Bluegrass Festival | Russell Springs | KY | United States | August | 3rd Weekend | 2 Days | Bluegrass | Music |
| Lake Itasca Family Music Festival | Lake Itasca | MN | United States | August | 1st Weekend | 3 Days | Family-friendly music | Music |
| Lake Martin Songwriter Festival | Alexander City | AL | United States | September | 4th Weekend | 4 Days | Singer-Songwriter, Americana, Folk and Country | Music |
| Lake Tahoe Reggae Festival | Lake Tahoe | CA | United States | August | 1st Weekend | 2 Days | Reggae | Music |
| Lakefront Music Fest | Prior Lake | MN | United States | July | 2nd Weekend | 2 Days | Variety | Music |
| Larryfest | LaFarge | WI | United States | August | 3rd Weekend | 3 Days | Bluegrass | Music |
| Las Vegas Family Bluegrass | Las Vegas | NV | United States | September | Last Weekend | 3 Days | Bluegrass | Music |
| Laurel Highlands Bluegrass Festival | Ligonier | PA | United States | June | Last Weekend | 3 Days | Bluegrass | Music |
| Laurel Hill Bluegrass Festival | Somerset | PA | United States | August | 3rd Weekend | 2 Days | Bluegrass | Music |
| Lester Flatt Celebration | Sparta | TN | United States | October | 2nd Saturday | 1 Day | Bluegrass | Music |
| Levitate Festival | Marshfield | MA | United States | July | 1st Weekend | 3 Days | Jam | Music |
| Lewis County Bluegrass Festival | Crawford | WV | United States | August | 3rd Weekend | 2 Days | Bluegrass | Music |
| Lightning Bug Music Festival | Valparaiso | IN | United States | September | 2nd Weekend | 2 Days | Indie, alternative, rock, with a diverse lineup across various genres | Music |
| Little Roy & Lizzy Music Festival | Lincolnton | GA | United States | May | 1st Weekend | 3 Days | Bluegrass | Music |
| Locomotion Fest | Felton | CA | United States | August | 1st Weekend | 3 Days | Jam, Bluegrass | Music |
| Lone Cedar Acres Bluegrass Festival | Pittsville | MD | United States | October | 4th Saturday | 1 Day | Bluegrass | Music |
| Lone Star Smokeout | Arlington | TX | United States | May | 1st Weekend | 3 Days | Country | Music |
| Long Beach Bluegrass Festival | Long Beach | CA | United States | May | 1st Saturday | 1 Day | Bluegrass | Music |
| Long Beach Jazz Festival | Long Beach | CA | United States | August | 2nd Weekend | 3 Days | Jazz | Music |
| Lost in Dreams Festival | Los Angeles | CA | United States | July | 2nd Weekend | 2 Days | Variety | Music |
| Lost Lands | Thornville | OH | United States | September | 3rd Weekend | 3 Days | Bass, Electronic | Music |
| Lost River Bluegrass Festival | Merrill | OR | United States | July | 2nd Weekend | 3 Days | Bluegrass | Music |
| Louisiana Folk Roots Festival | Natchitoches | LA | United States | September | 2nd Weekend | 3 Days | Folk, Americana, Roots, with a focus on Louisiana music traditions. | Music |
| Love RNB Festival | Los Angeles | CA | United States | September | 1st Weekend | 1 Day | R&B | Music |
| Lovegrass Music Festival | Wilson Lake | KS | United States | August | 2nd Weekend | 3 Days | Bluegrass | Music |
| Lucidity Festival | Bradley | CA | United States | April | 4th Weekend | 3 Days | Alternative, Electronic, Rock | Music |
