- 1 OneRepublic
- 2 One Direction
- 3 Oasis
- 4 Owl City
- 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 Ofenbach
- 14 Outlandish
- 15 Old Dominion
- 16 Orchestral Manoeuvres in the Dark
- 17 of Montreal
- 18 O-Town
- 19 Old Man Canyon
- 20 Overground
- 21 OU
- 22 ONUKA
- 23 Old Gods Of Asgard
- 24 Opeth
- 25 Of Monsters And Men
- 26 Oceanlab
- 27 Obituary
- 28 O.A.R.
- 29 Outloud
- 30 Outlawz