| Random Wisdom Limited | Professional & scientific | 2020 |
| Rank & File Theatre CIC | Education | 2023 |
| Raptuk Publishing Limited | Information & communication | 2017 |
| Ravika Properties Ltd | Real estate | 2025 |
| Ravn Aerospace UK Limited | Education | 2024 |
| RAW Business Consulting Services Ltd | Professional & scientific | 2010 |
| Rayner Diesel Services Limited | Wholesale & retail | 2003 |
| Rayners Limited | Other services | 1978 |
| RB (PWT) LLP | | 2017 |
| RBG Commercial Limited | Administrative & support | 1982 |
| RC Equine Veterinary Consultancy Ltd | Professional & scientific | 2015 |
| RC Equine Veterinary Holding Limited | Professional & scientific | 2021 |
| Reading Real Estate (UK) Limited | Real estate | 2015 |
| Ready Tours Limited | Administrative & support | 2018 |
| Readybus Limited | Transport & logistics | 2003 |
| Readygoset Limited | Administrative & support | 2025 |
| Real Estate Advisors Limited | Professional & scientific | 2017 |
| Real Estate Associates (Leatherhead) LP | | 2004 |
| Real Estate Associates (Northampton) LP | | 2006 |
| Real Estate Associates (Theale) LP | | 2005 |
| Real Estate Associates Limited | Real estate | 2002 |
| Real World Associates Limited | Professional & scientific | 1999 |
| Rebel Pizza Limited | Hospitality | 2021 |
| Rebl Data Limited | Information & communication | 2019 |
| Rebuild Groundwork & Construction Ltd | Construction | 2021 |
| Reco Algo Ltd | Information & communication | 2022 |
| Recovery in Mind 2016 CIC | Health & social care | 2016 |
| RECRUITS4U Ltd | Administrative & support | 2019 |
| Red Bridge Enterprise Limited | Professional & scientific | 2025 |
| Red Door Training Ltd | Administrative & support | 2014 |
| Red Spot Films Limited | Information & communication | 2015 |
| Red Thread Development Ltd | Professional & scientific | 2024 |
| Redcrest Enterprises Ltd | Construction | 1999 |
| Redcurrent Ltd | Professional & scientific | 2010 |
| Redfield Court (Phase II) Limited | Households | 1974 |
| Redfox Audio Visual Ltd | Administrative & support | 2021 |
| Redlands Property Services Ltd | Construction | 2011 |
| Redpace Ltd | Professional & scientific | 2012 |
| Redwood Psychology Limited | Education | 2018 |
| Reeny Associates Limited | Other services | 2016 |
| Reese Consulting Ltd | Administrative & support | 2024 |
| Regale Group Limited | Financial services | 2025 |
| Reggie’S Razors Ltd | Wholesale & retail | 2023 |
| Reglogix Limited | Public administration | 2026 |
| Regnumtek Ltd | Information & communication | 2025 |
| Regxel Solutions Limited | Wholesale & retail | 2025 |
| Reinventing Health Ltd | Health & social care | 2022 |
| Renartgades LLP | | 2025 |
| Renovation Projects Management Services Limited | Real estate | 2024 |
| Reserveocean Ltd | Administrative & support | 2024 |
| Residential Managing Agents (RMA) Ltd | Administrative & support | 2018 |
| Resiforge Ltd | Manufacturing | 2025 |
| Restrop Court Management Limited | Households | 1984 |
| Restrop Court Residents Company Limited | Real estate | 2000 |
| Restyled by SLC Ltd | Professional & scientific | 2021 |
| Retail Innovation Group Limited | Professional & scientific | 2015 |
| Retarus (UK) Ltd | Information & communication | 2011 |
| Revenue Works Limited | Professional & scientific | 2018 |
| Revium Corporate Services Limited | Administrative & support | 2016 |
| Revium Group Holdings Limited | Financial services | 2019 |
| Rezolutionz Limited | Professional & scientific | 2019 |
| RF & Vision Services Ltd | Information & communication | 2023 |
| RFF Loveridge Ltd | Administrative & support | 2020 |
| RFM Associates Limited | Professional & scientific | 2009 |
| RFR Projects Ltd | Professional & scientific | 2008 |
| RFR Residential Ltd | Real estate | 2024 |
| Rhizome Insights Limited | Information & communication | 2021 |
| Riaan Consultancy Ltd | Information & communication | 2015 |
| Rian Mobile Limited | Information & communication | 2007 |
| Ribbity Ltd | Real estate | 2021 |
| Richard Beynon,Limited | Administrative & support | 1921 |
| Richard Greenly Photography Limited | Professional & scientific | 1998 |
| Richard Markham Tax Ltd | Professional & scientific | 2018 |
| Richard Mccarthy Commercial Limited | Real estate | 2026 |
| Richard Mccarthy Developments Limited | Construction | 2025 |
| Richard Mccarthy Holdings Limited | Real estate | 2020 |
| Richard Mccarthy Properties Limited | Construction | 2025 |
| Richard O'Gorman Bloodstock Limited | Wholesale & retail | 1980 |
| Richard Piper Automotive Recruitment Limited | Administrative & support | 2019 |
| Richardson Commercial Ltd | Households | 2015 |
| Ricky's Driving School Ltd | Education | 2023 |
| Ride Electric Group Ltd | Professional & scientific | 2014 |
| Ridgeline Build Ltd | Construction | 2023 |
| Ridgeway Financial Services Limited | Financial services | 2000 |
| Ridgeway.Cloud Ltd | Information & communication | 2024 |
| Rieko Technologies Ltd | Wholesale & retail | 2019 |
| Rifeng UK Limited | Wholesale & retail | 2018 |
| Rigiflex Plastics Limited | Manufacturing | 2022 |
| Riguardino Ltd | Wholesale & retail | 2026 |
| Rio's Decorators Ltd | Construction | 2022 |
| Rise & Shine Window Cleaners Limited | Administrative & support | 2009 |
| Rising Rooted Ltd | Administrative & support | 2022 |
| Ritson Reid Limited | Transport & logistics | 2019 |
| Ritual Trading Limited | Wholesale & retail | 2026 |
| Rivar Limited | Real estate | 1964 |
| Rivar Sand & Gravel Limited | Wholesale & retail | 1981 |
| Rivendale Systems Limited | Information & communication | 1994 |
| Riverbeck Limited | Professional & scientific | 2003 |
| Riverbeck Semiconductor Limited | Extraterritorial | 2010 |
| Rivermead Trading Limited | Wholesale & retail | 2003 |