| Song/Tune Title | Book |
| On Top Of Old Smoky composed by Traditional | BPS |
| On Top Of Old Smoky F Major | LFS |
| On Wisconsin! G Major, composed by Carl Beck, W.T. Purdy | AAPSB2E |
| On Your Shoulder, Or A Private With A | BSWW42 |
| On `lop Of Old Smoky | SOPT3- |
| Once a Night | ECDT |
| Once I Had a Pumpkin | VFVY |
| Once I Had A Sweetheart | FSEV1 |
| Once I Had A Sweetheart | GEFM |
| Once I Had A Sweetheart | JBSB |
| Once I Had A Sweetheart | UFGSC |
| Once I Had A Sweetheart A Major, composed by Traditional | AFFEG |
| Once I Had A Sweetheart A Minor | AFAS |
| Once I Knew A Pretty Girl | JBSB |
| Once in a lifetime (82) | TPWM |