| O'Reilly Theatre | Dublin, Ireland | VenueView profile |
| O.L.V. ter Duinenkerk | Koksijde, Belgium | VenueView profile |
| O2ABC | Glasgow, United Kingdom | VenueView profile |
| Oakengates Theatre | Telford, United Kingdom | VenueView profile |
| Oakes Ames Memorial Hall | Easton, United States | VenueView profile |
| Oakland Central Station | Oakland, United States | VenueView profile |
| Oakland Scottish Rite Center | Oakland, United States | VenueView profile |
| Obecní dům (Municipal House) | Prague, Czech Republic | VenueView profile |
| Obere Fabrik Sissach | Sissach, Switzerland | VenueView profile |
| Oberfrankenhalle | Bayreuth, Germany | VenueView profile |
| Oberlandesgericht | Cologne, Germany | VenueView profile |
| Oberlandesgericht Köln | Cologne, Germany | VenueView profile |
| Oberlin College and Conservatory | Oberlin, United States | VenueView profile |
| Oberrheinhalle | Offenburg, Germany | VenueView profile |
| Obihiro City Community Hall | Obihiro, Japan | VenueView profile |
| Oblastnaya Filarmoniya (Областная филармония) | Orenburg, Russia | VenueView profile |
| Observatoire de Nice | Nice, France | VenueView profile |
| Observatory Hill Park | Sydney City, Australia | VenueView profile |
| Ocean City Music Pier | Ocean City, United States | VenueView profile |
| Octagon | Yeovil, United Kingdom | VenueView profile |
