| RG Transport(Reading) Ltd | Wholesale & retail | 2010 |
| RGT Carz Ltd | Wholesale & retail | 2026 |
| Rhino Club Limited | Professional & scientific | 2001 |
| Rialto Accelerated Leadership Index Limited | Information & communication | 2018 |
| Rialto Consulting Limited | Professional & scientific | 2013 |
| Ricardo Consulting LLP | | 2026 |
| Rich Services Ltd | Transport & logistics | 2024 |
| Richard Walker Geoscience Ltd | Professional & scientific | 2021 |
| Richman Investments Limited | Real estate | 2020 |
| Richmond Toys Ltd | Wholesale & retail | 1998 |
| Richvisuals Ltd | Professional & scientific | 2010 |
| Rickovery Limited | Administrative & support | 2020 |
| Rideworx Limited | Wholesale & retail | 2015 |
| Rideworx Service Limited | Wholesale & retail | 2022 |
| Ridgeway Electrical Contractors Ltd | Construction | 2018 |
| Riedel Communications Ltd | Information & communication | 2005 |
| Rieder Connection Ltd | Health & social care | 2023 |
| Riflesso Ltd | Construction | 2020 |
| Rightcar Motors Ltd | Wholesale & retail | 2025 |
| Rights and Remedies UK Ltd | Administrative & support | 2011 |
| Rightview Partners Limited | Professional & scientific | 2016 |
| Ringside Media Limited | Information & communication | 2020 |
| RIO Support Ltd | Health & social care | 2021 |
| Rising Social Limited | Information & communication | 2018 |
| Rivendell Technologies Limited | Administrative & support | 2002 |
| Riversight Ltd | Professional & scientific | 2016 |
| RJ Sparky Ltd | Manufacturing | 2026 |
| RJS Demolition Ltd | Construction | 2024 |
| RK Technik Limited | Information & communication | 2016 |
| RMD Operations Ltd | Hospitality | 2026 |
| RNR Chauffeurs Ltd | Transport & logistics | 2025 |
| Roar Services Ltd | Information & communication | 2021 |
| Rob's Engineering Ltd | Wholesale & retail | 2021 |
| Robert Harding Picture Library Limited | Professional & scientific | 1978 |
| Robert Price and Sons Glass Limited | Construction | 2018 |
| Roberts Parks Ltd | Administrative & support | 2019 |
| Robertson Macintosh Ltd | Professional & scientific | 2018 |
| Robertsons & Crawford Wills & Trusts Ltd | Administrative & support | 2020 |
| Robins Gate Bracknell Management Ltd | Construction | 2018 |
| Robinson Crusoe Management Company Limited | Households | 1995 |
| Robinwood (Sunningdale) Management Company Limited | Real estate | 2004 |
| Robson Barnes Ltd | Hospitality | 2015 |
| Robtech Engineering Consultants Limited | Manufacturing | 2012 |
| Roccotate Ltd | Health & social care | 2020 |
| Rochester Associates Ltd | Professional & scientific | 2024 |
| Rockford Industries Ltd | Administrative & support | 2020 |
| Rockrimmon Limited | Information & communication | 2009 |
| Rockwell Collins UK Financing LP | | 2009 |
| Rockwell Collins UK Limited | Wholesale & retail | 1955 |
| Rocky Autos Limited | Wholesale & retail | 2023 |
| Roco Brands Ltd. | Wholesale & retail | 2019 |
| Rococo Jewellery Ltd | Wholesale & retail | 2004 |
| Rodhouse Properties Limited | Real estate | 2021 |
| Rokime Limited | Construction | 2023 |
| Rolling Pictures Limited | Information & communication | 2020 |
| Rolling Productions Limited | Professional & scientific | 1998 |
| Roman Mews Management Company Limited | Households | 2008 |
| Roots 2 Shoots Tree Care Limited | Administrative & support | 2024 |
| Roscan Electronics Limited | Manufacturing | 1997 |
| Rose Cottages Mill Lane Management Ltd | Households | 2022 |
| Rose Pine Productions Limited | Information & communication | 2017 |
| Rose Technologies Limited | Information & communication | 2026 |
| Rose&Roots Ltd | Real estate | 2023 |
| Roseale and Company | Financial services | 2015 |
| Roseweir Consultancy Ltd | Administrative & support | 2015 |
| Rosewood Management Company Limited | Households | 1994 |
| Ross Fonternel Associates Limited | Professional & scientific | 2002 |
| Rossbe Ltd | Wholesale & retail | 2023 |
| Rota Systems Limited | Information & communication | 2013 |
| Roubaix Consulting Limited | Administrative & support | 2014 |
| Rouk Limited | Wholesale & retail | 2024 |
| Round Seven Ltd | Construction | 2022 |
| Rowgate Group Limited | Transport & logistics | 2016 |
| Rowley Alexander Ltd | Construction | 2024 |
| Rowney Sharman Project Consultants Limited | Professional & scientific | 1994 |
| ROY Wood Transits Limited | Wholesale & retail | 1973 |
| Roylance Estates Limited | Real estate | 2025 |
| Rpmgi Europe Limited | Information & communication | 2014 |
| Rqtrade Limited | Financial services | 2025 |
| RR Housing Limited | Real estate | 2023 |
| RRF Homes Limited | Real estate | 2026 |
| RS Dynamica Limited | Information & communication | 2021 |
| RSF Trading Ltd | Wholesale & retail | 2021 |
| Rsgupt Consultants Limited | Information & communication | 2013 |
| RT Safety Solutions Limited | Administrative & support | 2016 |
| RTK Family UK Limited | Administrative & support | 2025 |
| RTS Painting, Decorating and Renovations Ltd | Construction | 2016 |
| Rubex Properties Ltd | Real estate | 2016 |
| Ruby and Grace Ltd | Wholesale & retail | 2018 |
| Ruby Jewel Ltd | Hospitality | 2021 |
| Ruby Rose Beauty Ltd | Other services | 2013 |
| Rugbytots Wiltshire LLP | | 2017 |
| Rukra Estates (UK) Ltd | Construction | 2019 |
| Rukra Group Limited | Real estate | 2016 |
| Rukra Holdings Ltd | Financial services | 2025 |
| Runcowrun Ltd | Information & communication | 2026 |
| Rupert Dorgan Contractors Limited | Agriculture & fishing | 1956 |
| Ruscombe Artisan Food & Drink Ltd | Manufacturing | 2016 |
| Rushes Ltd | Information & communication | 2017 |
| Rushmoor Renewables Ltd | Professional & scientific | 2025 |