| Regatta FS 4 Ltd | Financial services | 2024 |
| Regency Real Estates Limited | Real estate | 2012 |
| Regulus Iter Ltd | Real estate | 2025 |
| Reliance IT Limited | Information & communication | 2010 |
| Reliance Pro Ltd | Construction | 2022 |
| Relimax Limited | Professional & scientific | 2009 |
| Renascentia Property Management Limited | Real estate | 2015 |
| Repro Group Holdings Ltd | Financial services | 2015 |
| Repro Recycling Limited | Administrative & support | 2015 |
| RES Novae | Information & communication | 2008 |
| Resilience Filter Limited | Information & communication | 2025 |
| Resolution Coaching the Way Forward Limited | Other services | 2020 |
| Resonata Music Ltd | Information & communication | 2013 |
| Resorcerers Limited | Professional & scientific | 2011 |
| Rethink Coaching and Consulting Ltd | Professional & scientific | 2020 |
| Retsol Ltd | Wholesale & retail | 2024 |
| Reuben Properties Limited | Real estate | 2023 |
| Reveal Services (Security) Ltd | Professional & scientific | 2017 |
| Revival Corporate Cleaning Limited | Administrative & support | 2006 |
| Reward Connected Limited | Administrative & support | 2010 |
| RGA Media Limited | Professional & scientific | 2024 |
| Rgas Heating Solutions Ltd | Construction | 2025 |
| RGP Dental Care Ltd | Professional & scientific | 2012 |
| RGS Homes Limited | Real estate | 2025 |
| Rhea Property Ltd | Real estate | 2022 |
| Richard Brown Property Consultancy Limited | Real estate | 2014 |
| Richard Eaton-Hart Consulting Limited | Real estate | 2025 |
| Richard Fawdry Consulting Ltd | Professional & scientific | 2018 |
| Richard Malcolm Consulting Ltd | Information & communication | 2026 |
| Richify Limited | Real estate | 2024 |
| Richkim Ltd | Wholesale & retail | 2025 |
| Ridhima Limited | Information & communication | 2013 |
| Right Compliance Limited | Other services | 2023 |
| Right Contract Services Limited | Administrative & support | 2008 |
| Right Track Installations Limited | Construction | 2016 |
| Rigita Ltd | Other services | 2019 |
| Rimner Enterprises Ltd | Real estate | 2019 |
| Rirk Limited | Wholesale & retail | 2023 |
| Risborough Plant Services (Holdings) Limited | Real estate | 1965 |
| Rise Fintech Limited | Information & communication | 2014 |
| Ritu Ltd | Wholesale & retail | 2006 |
| River Cottages Wroxham Limited | Hospitality | 2023 |
| Riverfront Landscaping Limited | Administrative & support | 2024 |
| Rivierre Limited | Information & communication | 2017 |
| RMC Solutions Limited | Professional & scientific | 2025 |
| RMG Electrical Ltd | Construction | 2023 |
| Road Tyres Ltd | Wholesale & retail | 2010 |
| Roald Dahl's Marvellous Children's Charity | Professional & scientific | 2010 |
| ROB Fyfe Consulting Limited | Professional & scientific | 2009 |
| Robert James Partnership Limited | Real estate | 1985 |
| Robertson Jones Publishing Limited | Information & communication | 2025 |
| Robsons (Amersham) LLP | | 2005 |
| Robsons Estate Agents Limited | Professional & scientific | 1987 |
| Rocafort Limited | Financial services | 2025 |
| Roche Industries Limited | Professional & scientific | 2009 |
| Rochester Hotel General Partner Limited | Administrative & support | 2017 |
| Rochester Hotel L.P. | | 2017 |
| Rochester Hotel Nominee Limited | Professional & scientific | 2017 |
| Rockall Focus Ltd | Information & communication | 2025 |
| Rodgers Specialist Lettings Limited | Real estate | 2021 |
| Roger Rawlinson & Associates Ltd | Administrative & support | 2014 |
| Rohrback Cosasco Systems UK Limited | Wholesale & retail | 2003 |
| Rokwell Records Ltd | Information & communication | 2025 |
| Roman Bilinski Fashion Ltd | Professional & scientific | 2025 |
| Roqit Payments Ltd | Information & communication | 2025 |
| Roromac Limited | Real estate | 2003 |
| Rosaris FM Ltd | Extraterritorial | 2023 |
| Rosaris Ltd | Information & communication | 2016 |
| Rose & Harrison Ltd | Real estate | 2025 |
| Rosedale College Community Enterprise Limited | Education | 2008 |
| Roset (UK) Limited | Wholesale & retail | 1980 |
| Rossify Ltd | Administrative & support | 2023 |
| Rosteel Limited | Construction | 2018 |
| Rostrum Crisis Services Limited | Information & communication | 2021 |
| Rostrum Limited | Information & communication | 2003 |
| Rostrum Ventures Limited | Information & communication | 2021 |
| Routa Digital UK Ltd | Information & communication | 2024 |
| RPC Developments Ltd | Construction | 2014 |
| RPC Homes Ltd | Construction | 2021 |
| RSG Consultancy Limited | Professional & scientific | 2020 |
| Rtyc Group Ltd | Real estate | 2021 |
| Rubium Enterprise UK Ltd | Wholesale & retail | 2026 |
| RUS Enterprises Ltd | Professional & scientific | 2018 |
| RUT Infotech Ltd | Information & communication | 2022 |
| RV Investments Ltd | Real estate | 2017 |
| RV Landmark Limited | Real estate | 2025 |
| S J W Sunbury Ltd | Real estate | 2022 |
| S K Interior Solutions Limited | Administrative & support | 2008 |
| S L Anderson (Chemists) Limited | Wholesale & retail | 1994 |
| S M Eveleigh Design Ltd | Professional & scientific | 2023 |
| S Perrin Ltd | Arts & recreation | 2015 |
| S-Chelate Crop Nutrition Limited | Extraterritorial | 2017 |
| S.O.U.L. by Gagan Singh Ltd | Other services | 2021 |
| S2K Consultancy Service Ltd | Information & communication | 2018 |
| S3 Infotech Ltd | Information & communication | 2007 |
| Sa-Cse Ltd | Professional & scientific | 2012 |
| Saas Investments Limited | Real estate | 2022 |
| SAB Embassy Limited | Hospitality | 2023 |
| Sackville Securities Limited | Real estate | 1986 |
| Sadowitz Consulting Ltd | Professional & scientific | 2022 |