- 1 Otilia
- 2 Oh Susanna
- 3 Orkid
- 4 Oh Land
- 5 Odessa
- 6 Olivia Belli
- 7 Olivia Dean
- 8 OR3O
- 9 Olga Lounova
- 10 Olivia Addams
- 11 Olivera
- 12 Olivia Herdt
- 13 Ony
- 14 Origa
- 15 Oceana
- 16 Otis McDonald
- 17 OSTON
- 18 ooxygen
- 19 Odetta
- 20 Ornella Vanoni
- 21 Okay Kaya
- 22 One-T
- 23 Olivia Broadfield
- 24 Olivia Ruiz
- 25 Ofelia
- 26 Olivia Newton-John
- 27 Olivia O'Brien
- 28 Orianthi
- 29 Ofelia Del Rosal
- 30 Olivia Foa'i