- 1 OneRepublic
- 2 One Direction
- 3 Oasis
- 4 Owl City
- 5 O-Zone
- 6 One Voice
- 7 OU
- 8 Oh Wonder
- 9 One-T And Cool-T
- 10 Of Monsters And Men
- 11 Oh The Larceny
- 12 Outkast
- 13 Ofenbach
- 14 Odesza
- 15 Our Last Night
- 16 Overground
- 17 O-Town
- 18 of Montreal
- 19 Oceanlab
- 20 Oberhofer
- 21 Old Gods Of Asgard
- 22 ONUKA
- 23 Orchestral Manoeuvres in the Dark
- 24 OK Go
- 25 Origen
- 26 Obituary
- 27 Outloud
- 28 Orbital
- 29 Ozomatli
- 30 Outlawz