| Roseberry Court Management Company Limited | Households | 1983 |
| Roseberry Road BS5 Investments Ltd | Real estate | 2026 |
| Rosecliff Investments Limited | Financial services | 2023 |
| Rosedale Lodge Management Co. Limited | Real estate | 1996 |
| Rosegarth Property Limited | Real estate | 2025 |
| Rosemary Coldstream Garden Design Limited | Administrative & support | 2011 |
| Rosenberg.Media Ltd | Professional & scientific | 2025 |
| Rosie Holledge Ltd | Information & communication | 2017 |
| Rosier Limited | Administrative & support | 2004 |
| Roslin Consulting Limited | Information & communication | 2021 |
| Ross ROY Ltd | Professional & scientific | 2025 |
| Rossazzurri Limited | Professional & scientific | 2009 |
| Rossco Services Ltd | Information & communication | 2023 |
| Rosser & Russell Maintenance Limited | Construction | 1968 |
| Rosy Ribbons Ltd | Wholesale & retail | 2024 |
| Roukcorp Limited | Professional & scientific | 2015 |
| Round Square Consultancy Ltd | Professional & scientific | 2019 |
| Rounders Limited | Manufacturing | 2025 |
| Roundhouse Events Services Ltd | Hospitality | 2025 |
| Roundhouse Property Investments Ltd | Real estate | 2016 |
| Roundmen (Trevol) Ltd | Energy | 2019 |
| Roundmen Limited | Extraterritorial | 1987 |
| Routeline Ltd | Transport & logistics | 2025 |
| Rowan Gardens Limited | Administrative & support | 2022 |
| Rowlands Estates Services Limited | Real estate | 2020 |
| Roxeth Mead Management Ltd. | Households | 1992 |
| ROY Events Ltd | Other services | 2017 |
| ROY NUT Foods Ltd | Other services | 2017 |
| Roya Services Ltd | Information & communication | 2024 |
| Royalduke Limited | Wholesale & retail | 2026 |
| Roys Property Investments Limited | Real estate | 2019 |
| Rozina ALI Ltd | Health & social care | 2021 |
| RP Consulting Ltd | Professional & scientific | 2018 |
| Rpes Projects Ltd | Construction | 2026 |
| Rpgbiz Limited | Administrative & support | 2010 |
| Rpix Ltd | Professional & scientific | 2025 |
| RPL Props Limited | Construction | 2023 |
| RPM Sound Ltd | Information & communication | 2021 |
| RPP Watford Limited | Hospitality | 2016 |
| Rppf Limited | Real estate | 2017 |
| Rpstock Ltd | Wholesale & retail | 2019 |
| RPT Building Services Limited | Construction | 2015 |
| RPT Electrical Supplies Limited | Wholesale & retail | 2021 |
| RR Builds Ltd | Construction | 2023 |
| RR Express Limited | Hospitality | 2020 |
| RR Landscape Solutions Ltd | Administrative & support | 2013 |
| Rrethi Ltd | Real estate | 2023 |
| RRH Holdings Ltd | Financial services | 2023 |
| RRS Technology Solutions Ltd | Information & communication | 2024 |
| RS Group of Companies Limited | Real estate | 2025 |
| RS Host Solutions Ltd | Real estate | 2026 |
| RSC Surfacing Group Ltd | Construction | 2026 |
| RSD Financial Services Ltd | Professional & scientific | 2013 |
| RSI Solutions Ltd | Administrative & support | 2018 |
| RSJ Consultancy Services Ltd | Professional & scientific | 2025 |
| RSJ Tech Ltd | Information & communication | 2017 |
| RSK44 Ltd | Construction | 2020 |
| RSL Infotech Ltd | Information & communication | 2011 |
| RSN Financial Solutions Ltd | Financial services | 2023 |
| Rsna Consultants Ltd | Professional & scientific | 2021 |
| Rsquarevp Ltd | Information & communication | 2023 |
| RT Building Contractors Ltd | Construction | 2019 |
| RT Consultancy Ltd | Information & communication | 2019 |
| RT Infotek UK Ltd | Information & communication | 2024 |
| RT Network Solutions UK Ltd | Information & communication | 2025 |
| RT Surveying & Project Management Ltd | Professional & scientific | 2019 |
| RTB Technologies UK Limited | Information & communication | 2024 |
| Rtecheng Limited | Real estate | 2018 |
| RTJ IT Solutions Ltd | Information & communication | 2017 |
| Ruach (UK) Ltd | Wholesale & retail | 2007 |
| Rubberroofingservices Ltd | Construction | 2016 |
| Ruben Express Ltd | Transport & logistics | 2022 |
| Rubes PR Consultancy Ltd | Professional & scientific | 2013 |
| Rubicon-Tech Ltd | Administrative & support | 2017 |
| Ruda 78 Limited | Construction | 2025 |
| Ruda Developments Limited | Construction | 2025 |
| Rudkin Developments Ltd | Real estate | 2022 |
| Rudkin Driving Express PVT Ltd | Transport & logistics | 2016 |
| Rudra Beauty Ltd | Other services | 2024 |
| Rudra Services Ltd | Professional & scientific | 2018 |
| Rudra Technologies Limited | Information & communication | 2016 |
| Rudraksh Construction Ltd. | Other services | 2021 |
| Rudransh Investments Ltd | Real estate | 2026 |
| Rudy's Company Ltd | Information & communication | 2018 |
| RUF TUF Limited | Wholesale & retail | 2015 |
| Ruffles 79 London Ltd | Wholesale & retail | 2023 |
| Ruffus X Ltd | Transport & logistics | 2023 |
| RUG Addiction Limited | Wholesale & retail | 2002 |
| Ruhi Catering Limited | Hospitality | 2025 |
| Ruhi Properties Ltd | Real estate | 2022 |
| Ruislip Tyre Services Limited | Manufacturing | 2008 |
| Ruislip Windows and Doors Limited | Construction | 1995 |
| Ruisoft Ltd | Information & communication | 2014 |
| Rujay Ltd. | Administrative & support | 2017 |
| Rukhmah Saleem Ltd | Professional & scientific | 2016 |
| Rukt Limited | Real estate | 2023 |
| Rule Britannia Limited | Other services | 2026 |
| Rumis Holdings Ltd | Financial services | 2024 |
| Rumy Limited | Real estate | 2022 |
| Run Cargo Ltd | Transport & logistics | 2018 |