| O.U.R Brand Music Label Inc. | — | 2016 | Imprint |
| Obese Records | Australia | 2002 | Original Production |
| Objectif Prod | France | — | Production |
| Ockword Records LLC | United States | 2018 | Imprint |
| Oda Bizness | France | — | Production |
| OKAY Recs | — | 2017 | — |
| Oligarchy Records | France | — | Production |
| Om Records | — | 1995 | Original Production |
| On the Corner | France | — | Original Production |
| OpenPlay | — | January 14, 2019 | Production |
| Opium | United States | 2019 | Original Production |
| Opium | — | — | — |
| Original Dub Gathering | France | 2005 | — |
| Original Muzik | — | November 15, 2018 | Distributor |
| Oscillation Records | — | — | — |
| Ostgut Ton | — | — | — |
| Oto10dakt | France | April 2007 | Production |
| Ouesch Productions | France | — | Production |
| Outlaw Recordz | United States | — | Original Production |
| OUTSOUNDING Entertainment | — | 2015 | Original Production |
| OUTTAHELL | — | July 3, 2019 | Publisher |
| OVO Sound | Canada | 2012 | Original Production |
| OVO Sound | — | — | — |