- 1 Olivia Rodrigo
- 2 Olivia Dean
- 3 Olivia Addams
- 4 OR3O
- 5 One T
- 6 Orianthi
- 7 Oonagh
- 8 Otilia
- 9 Oly
- 10 Orla Fallon
- 11 Ofelia K
- 12 Olive Beat
- 13 Oceana
- 14 Olivia Newton-John
- 15 Olivia Herdt
- 16 ooxygen
- 17 oleta adams
- 18 Ofrin
- 19 Olivia O'Brien
- 20 Origa
- 21 Olivia Broadfield
- 22 Oh Susanna
- 23 Orenda Fink
- 24 Oh Land
- 25 Olivia Theresa Longott
- 26 Olivia Henken
- 27 Ornella Vanoni
- 28 Odetta
- 29 Omara Portuondo
- 30 Ophélie Winter