- 1 OneRepublic
- 2 Oasis
- 3 One Direction
- 4 Owl City
- 5 O-Zone
- 6 Oh The Larceny
- 7 Oh Wonder
- 8 OK Go
- 9 Odesza
- 10 Outkast
- 11 Oceanlab
- 12 Omnium Gatherum
- 13 Our Last Night
- 14 Overground
- 15 One-T And Cool-T
- 16 Opeth
- 17 Of Monsters And Men
- 18 Origen
- 19 Old 97's
- 20 Old Gods Of Asgard
- 21 ONUKA
- 22 Orchestral Manoeuvres in the Dark
- 23 O-Town
- 24 of Montreal
- 25 Oomloud
- 26 Oomph!
- 27 Ofenbach
- 28 Oneira
- 29 Our Lady Peace
- 30 Ocean Colour Scene