| Integral IT | |
| Integral Network Solutions | South Yorkshire |
| Integralist | |
| Integrated Applications Ltd | South Yorkshire |
| Integrated Design Techniques Ltd | Tyne and Wear |
| Integrated Electronics Ltd | Hampshire |
| Integrated Environmental Solutions Ltd | Glasgow |
| Integrations.co.uk | Essex |
| Integrety Software Systems Ltd | Buckinghamshire |
| Integrity Connect | |
| Integrity UK | |
| Intelak Hub | |
| Intelance | |
| Intelecom Ltd | Cambridgeshire |
| Intelicle Ltd | |
| Intelistyle | Greater London |
| Intelivita Ltd | |
| Intellect Computers | Greater Manchester |
| IntellectoKids Ltd | |
| Intellek | Somerset |
| Intellia Ltd | Falkirk |
| Intellicore Ltd | |
| Intelliflo Ltd | |
| Intelligence Fusion | |
| Intelligence Software | Belfast |
| Intelligent AI Ltd | |
| Intelligent Business Strategies Ltd | Cheshire |
| Intelligent Delivery Solutions | |
| Intelligent Growth Solutions Ltd | |
| Intelligent Health AI Ltd | |
| Intelligent IT Solutions | Cardiff |
| Intelligent OMICS Ltd | |
| Intelligent Plant Ltd | |
| Intelligent Positioning | |
| Intelligent Reach Ltd | |
| Intelligent Retail Ltd | Berkshire |
| Intelligent Vending Ltd | |
| Intelligent Web Solutions Ltd | |
| Intellihep Ltd | |
| IntelliSoftware Ltd | Dorset |
| Intellling Ltd | |
| Intent | |
| IntentHQ | |
| Inter Vivos Digital Marketing Ltd | |
| Inter-Arc | |
| Inter-Logic | Norfolk |
| Interact Software Ltd | West Sussex |
| Interactive Advertising Ltd | Berkshire |
| Interactive Education Solutions Ltd | West Midlands |
| Interactive Information Services | Shropshire |