| 24515 | O-Level GCE/CSE Maths Test | ZX-Spectrum 48K | English |
| 19404 | O-Level Revision Aid | ZX-Spectrum 48K | English |
| 20281 | O-Level Technical Drawing | ZX-Spectrum 48K | English |
| 34608 | O-Puzz Attack | ZX-Spectrum 48K | English |
| 26573 | O-Trix | ZX-Spectrum 48K | English |
| 3499 | O.K. Yah! | ZX-Spectrum 48K | English |
| 14477 | O.S. Quiz | ZX-Spectrum 48K | English |
| 19295 | O/A-Level Physics Definitions | ZX-Spectrum 48K | English |
| 32302 | OKNOTOK | ZX-Spectrum 48K | English |
| 17912 | ONELINERS | ZX-Spectrum 48K | English |
| 34298 | OPZ | ZX-Spectrum 48K | English |
| 39230 | ORG | ZX-Spectrum 48K | English |
| 27143 | ORGANize | ZX-Spectrum 48K | English |
| 35893 | ORIGMATR | ZX-Spectrum 48K | Hungarian |
| 40829 | OSCAR-9 Azimuth/Elevation Table | ZX-Spectrum 48K | English |
| 11316 | OTAN Alerta! + War Zone | ZX-Spectrum 48K | Spanish |
| 17606 | OTWOC | ZX-Spectrum 48K | English |
| 39622 | OUT 254 | ZX-Spectrum 48K | English |
| 25868 | OXO | ZX-Spectrum 48K | English |
| 19549 | OXO Addition and Subtraction | ZX-Spectrum 48K | English |