- 1 OneRepublic
- 2 One Direction
- 3 Oasis
- 4 Owl City
- 5 O-Zone
- 6 OK Go
- 7 Oh Wonder
- 8 Odesza
- 9 Oh The Larceny
- 10 One-T And Cool-T
- 11 Overground
- 12 ONUKA
- 13 Our Last Night
- 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 OtherView
- 23 Orbital
- 24 of Montreal
- 25 Ozomatli
- 26 Of Monsters And Men
- 27 OZMA
- 28 O-Town
- 29 Outkast
- 30 Outlawz