- The Last Hombres -- The Lilly Brothers
- The Lincoln Penny Orchestra -- The Long Decline
- The Long Goners -- The Lucky Tomblin Band
- The Lumineers -- The Maryhillbillys
- The Masked Cowboy Band -- The Meat Purveyors
- The Mellors -- The Millionaires
- The Milo Twins -- The Mountjoys
- The MTK Band -- The Nashville Bluegrass Band
- The Nashville Bluegrass Singers -- The Nervous Wreckers
- The Nettles Brothers String Band -- The Normaltown Flyers
- The North Union -- The Old Boot Band
- The Olsten Brothers Band -- The Osborne Brothers
- The Outlaws -- The Paul Shearer Band