| 42736 | Invaders | ZX81 16K | English |
| 32025 | Invaders | ZX81 16K | English |
| 43666 | Invasion | ZX81 16K | German |
| 28998 | Invasion | ZX81 16K | Dutch |
| 28993 | Invasion Force | ZX81 16K | English |
| 44511 | Invasion Force | ZX81 16K | English |
| 31938 | Invasion Force - Chroma Edition | ZX81 16K | English |
| 28563 | Invasores | ZX81 16K | Spanish |
| 43484 | Invasores do Espaço | ZX81 16K | Portuguese |
| 31687 | Inventions 1 | ZX81 16K | - |
| 31688 | Inventory Control | ZX81 16K | - |
| 31689 | Inventory Control | ZX81 16K | - |
| 29000 | Inversion | ZX81 16K | English |
| 37569 | Inverter Routine | ZX81 16K | English |
| 40598 | Investment Appraisal | ZX81 16K | English |
| 41225 | Invincible | ZX81 16K | English |
| 37116 | Invincible Island ZX81 Edition | ZX81 16K | English |
| 29001 | Irrgarten | ZX81 16K | German |
| 43843 | Irrgarten 3D | ZX81 16K | German |
| 29002 | Island Kingdom | ZX81 16K | English |