| Reflectdigital | |
| Reflection Creative Media | |
| Reflex Arc | |
| Reflex Computer Recruitment Ltd | Surrey |
| Reflex Planing | |
| Reflex Studios | Belfast |
| Reflexology Space London | |
| Reform Corp Solutions | |
| Refractiv Ltd | |
| Refresh Cartridges | Devon |
| Refresh Studio | South Yorkshire |
| Refurbished Laptops | Wiltshire |
| ReGen | Devon |
| Regent's University London | Greater London |
| Regis IT Ltd | West Sussex |
| Regolithix Ltd | |
| Regulatory Genome Development Ltd | |
| Rehabstudio Ltd | |
| Reincubate Ltd | |
| Reivertech Ltd | |
| Rejuvenate Digital | |
| RElab | |
| Relation Therapeutics | |
| Relative Insight Ltd | |
| Relative Marketing | |
| Relax Telecom | |
| Relay Technologies Ltd | |
| RelChron Ltd | Fife |
| Release Technologies | Edinburgh |
| Relec Electronics Ltd | Dorset |
| Reliance Big Entertainment (UK) Pvt Ltd | Warwickshire |
| Reliance Precision Ltd | |
| Reliance Technologies Ltd | |
| Reliass | Hampshire |
| Relo | |
| Reload Digital Ltd | Greater London |
| Relocateme.eu | Greater London |
| RelonChem Ltd | |
| Remarkable Group International Ltd | |
| Remedian IT Solutions | |
| Remedian IT Solutions Ltd | Greater Manchester |
| Remedy HCMS Ltd | Surrey |
| Remedy IT Ltd | Devon |
| Remitech Ltd | |
| Remote New Media | Shropshire |
| Remote Skills Engineering Group | |
| Remote Tech Ltd | |
| Remoter | |
| Remotes4u (UK) | South Yorkshire |
| Remotestar Ltd | |