- 1 OneRepublic
- 2 Owl City
- 3 One Direction
- 4 Oasis
- 5 O-Zone
- 6 Oh Wonder
- 7 Oh The Larceny
- 8 Odesza
- 9 One-T And Cool-T
- 10 OK Go
- 11 Outkast
- 12 Origen
- 13 Orchestral Manoeuvres in the Dark
- 14 Our Lady Peace
- 15 Oceanlab
- 16 Ocean Colour Scene
- 17 Oh No! Oh My!
- 18 Obituary
- 19 O.A.R.
- 20 Oceana
- 21 Outloud
- 22 Orbital
- 23 of Montreal
- 24 Ozomatli
- 25 Of Monsters And Men
- 26 Overground
- 27 OZMA
- 28 Our Last Night
- 29 O-Town
- 30 Outlawz