| The Olympus Mons |
| The OM |
| The OM Sound |
| The OM Sound & Sex Laser |
| The OM Sound, T-Rav the Transformer |
| The Omaha Folk |
| The OMB Twins |
| The Omega Man Collective |
| The Omegamegs |
| The Omen |
| The OMG Girlz |
| The Ominous Seapods |
| The Omniscient |
| The Omy |
| The On the Line All-Stars |
| The Once |
| The Once Band |
| The One |
| The One After None |
| The One AM Radio |
| THE ONE DA |
| The One Eighties |
| The one from Rayn |
| The One Hundred |
| The One I Ever Had |
| The One Keon |
| THE ONE Lavic |
| The One Soc Soc Monkeys |
| The one that |
| The One They Fear |
| The One Tonic |
| The One Who Sings |
| The One World Ensemble |
| The One You Loved |
| The Oneill Twins |
| The Ones |
| The Onesies |
| The Onirist |
| The Only |
| The Only Boy to Sink a Ship |
| The Only Carnell |
| The only children |
| The Only Chris Covert |
| The Only Element |
| The Only Ghost in Town |
| The Only Makhaya |
| The Only Menace |
| The Only Meta Gold |
| The Only Ocean |
| The Only Ones |
| The Only Seven |
| The Only Verse |
| The Only VIC |
| The Only Zayy |
| The only1 |
| The Onomatopoets |
| The Onzio |
| The Oofs |
| The Oozes |
| The Open End |
| The Open Hearts |
| The Open Minds |
| The Opener |
| The Opening Act |
| The Opera |
| The Operation M.D. |
| The Ophelias |
| The OPM Hitmen |
| The Opposite of Sad |
| The Opposite Tapes |
| The Opposites |
| The Ops |
| The Optimistic Nihilist |
| The Optimystik |
| The Option |
| The Options |
| The Opus |
| The oracl |
| The Oracle |
| THE ORAL CIGARETTES |
| The Orange Box |
| The Orange Girl |
| The Orange Goodness |
| The Orange Lights |
| The Orange Peeling Committee |
| The Orange Peels |
| The Orange Teeth |
| The Orange Tiles |
| The Orangu-Tones |
| The Orators |
| The Orb |
| The Orcastrator |
| The Orchard |
| The Orchestra |
| The Orchestrator |
| The Orchids |
| The Order of the Diamond |
| The Order Of White Lotus, Acca Flame, Alexandra Msotra, Chexx, Flex Gvng, Kxngslyza & Pepper Black |
| The Ordinaires |
| The Ordinary Boys |
