- OVERPROTECTED – Britney Spears
- OVER THE RAINBOW – Judy Garland
- OUTSIDE – C Harris & E Goulding
- OUR LAST SUMMER – Abba
- OUR DAY WILL COME – Ruby & The Romantics
- ORDINARY PEOPLE – John Legend
- OOPS I DID IT AGAIN – Britney Spears
- ONLY YOU – Yazoo
- ONLY YOU – The Platters
- ONLY TIME – Enya
- ONLY THE LONELY – Roy Orbison
- ONE WAY TICKET – Neil Sedaka
- ONE OF US CANNOT BE WRONG – Leonard Cohen
- ONE OF US – Abba
- ONE NIGHT – Elvis Presley
- ONE MORE NIGHT – Phil Collins
- ONE MOMENT IN TIME – Whitney Houston
- ONE FOR MY BABY – Frank Sinatra
- ONE DAY I’LL FLY AWAY – Randy Crawford
- ONE CALL AWAY – Charlie Puth
- ONE AND ONLY – Adele
- ON THE SUNNY SIDE OF THE STREET – Frank Sinatra
- ON MY OWN – Patti Labelle
- ON MY OWN – Lea Salonga
- OLIVER'S ARMY – Elvis Costello
- OH PRETTY WOMAN – Roy Orbison
- OH DARLING – The Beatles
- OH BOY – Buddy Holly
- ODE TO BILLY JOE – Bobby Gentry
- OCTOPUS’S GARDEN – The Beatles
- OB LA DI OB LA DA – The Beatles