| Westcountry Media (UK) Ltd | Somerset |
| Westcut Engineering Ltd | |
| Westend WiFi Ltd | |
| Western Aspect | Bristol |
| Western Business Systems Ltd | Lancashire |
| Western Isles Web Services Ltd | Comhairle nan Eilean Siar |
| Westgate Communications Ltd | Kent |
| Westminster Group plc | Oxfordshire |
| Westside IT Solutions | |
| Westside Supplies | West Sussex |
| WestWon Ltd | |
| Westwood Associates Ltd | |
| Westwood Global Energy Group | |
| Westwood Rock Ltd | |
| Weuno Technoloiges | |
| WeVee | |
| Wexler | |
| Weybridge IT | Surrey |
| Weztec | Staffordshire |
| WG Partners | |
| Whale Marketing | |
| what3words | |
| WHATJOBS? | |
| WHCLS | |
| WHD Solutions | |
| WheelAir | |
| Whering | |
| Whimsy Games Ltd | |
| Whisk | West Midlands |
| White Digital | County Durham |
| White Fire Design Ltd | |
| White Fluffy Cloud Ltd | |
| White Had Web Design | Greater London |
| White Heat Design | Greater London |
| White Horse Capital | |
| White Label Crowdfunding | West Yorkshire |
| White Label Solutions | |
| White Rose Software | West Yorkshire |
| White Space Advertising Ltd | |
| White Star Capital | |
| White Status | Leicestershire |
| Whiteboardmaths.com | Lincolnshire |
| Whitedog | Staffordshire |
| Whitefish Marketing Ltd | |
| Whitehall Media Ltd | |
| Whitehouse Communications | |
| Whiteland Engineering Ltd | |
| WhiteNoise Media | |
| Whiteoaks International | |
| Whitesmith | |