| 574. Oklou | Guitar, Marimba, Piano, Recorder, Vocals | 1 |
| 574. Olabiyi Julius | Keys | 1 |
| 574. Old Crow Medicine Show | Featured Artist | 1 |
| 574. Ole Kirkeng | Bass | 1 |
| 574. Olena Tsybulska | Drums, Vocals | 1 |
| 574. Olga I. González | Background Vocals, Shaker, Tambourine | 1 |
| 574. Oli Harris | Cello | 1 |
| 574. Oli Jefferson | Drums | 1 |
| 574. Oli Langford | Violin | 1 |
| 574. Olive Hannah | Drums | 1 |
| 574. Oliver "Tuku" Mtukudzi | Featured Artist | 1 |
| 574. Oliver Bates Craven | Electric Guitar, Fiddle, Vocals | 1 |
| 574. Oliver Pinnell | Guitar | 1 |
| 574. Oliver Tuttle | Trombone | 1 |
| 574. Olivia 'Livi Lovez' Williams | Vocals | 1 |
| 574. Olivia Donalson | As Anna Of Cleves, Vocals | 1 |
| 574. Olivia Ivory Jean Walker | Vocals | 1 |
| 574. Olivia Tapia | Vocals | 1 |
| 574. Olivia Walker | Vocals | 1 |
| 574. Olivia Williams | Vocals | 1 |
| 574. Olivier St.Louis | Guitar, Vocals | 1 |
| 574. Ollella | Featured Artist | 1 |
| 574. Olof Arnalds | Featured Artist | 1 |
| 574. Olu Odubiro | Bass | 1 |
| 574. Olya Prohorova (Violin) | Musician | 1 |