| RTH Traders Limited | Wholesale & retail | 2006 |
| Rtig Inform Limited | Transport & logistics | 2022 |
| Rtlt Ltd | Information & communication | 2009 |
| RTM Consultancy Ltd | Professional & scientific | 2014 |
| RTN Clayton Tankers Limited | Manufacturing | 2013 |
| RTN Clayton Vallely Limited | Manufacturing | 2007 |
| RTR Business Services Limited | Professional & scientific | 2007 |
| RTW Digital Limited | Administrative & support | 2021 |
| RTY Wholesale Trade Ltd | Construction | 2018 |
| Rub-A-Dub RUB Ltd | Wholesale & retail | 2024 |
| Ruban Convenience Store Ltd | Wholesale & retail | 2024 |
| Rubans Convenience Store Ltd | Wholesale & retail | 2024 |
| Rubber Components (Stalybridge) Limited | Extraterritorial | 2009 |
| Rubber Gloves Cleaning Services Ltd | Administrative & support | 2018 |
| Rubber Safety Hygiene (Group) Limited | Wholesale & retail | 1990 |
| Rubbie Limited | Health & social care | 2019 |
| Rubble Properties Limited | Real estate | 2013 |
| Rubeez Restaurant Ltd | Hospitality | 2015 |
| Ruben Ferreira Ltd | Education | 2022 |
| Rubicon Software Consultants Limited | Information & communication | 2004 |
| Rubix Detailing & PPF Ltd | Wholesale & retail | 2025 |
| Rubix Detailing Ltd | Wholesale & retail | 2016 |
| Rubix Films Limited | Information & communication | 2020 |
| Rubrica Holdings Ltd | Financial services | 2026 |
| Ruby House Management Limited | Households | 1983 |
| Ruby Lounge Ltd | Extraterritorial | 2009 |
| Ruby Roofing & Building Limited | Construction | 2016 |
| Rubyeventsuk Ltd | Hospitality | 2026 |
| RUC Trading Ltd | Wholesale & retail | 2022 |
| Ruckstones Property Trading Ltd | Real estate | 2025 |
| Ruco UK Limited | Professional & scientific | 2001 |
| Ruddock Ashton International Ltd | Arts & recreation | 2021 |
| Rudra Perfusion Services Ltd | Health & social care | 2023 |
| Rudysasi Limited | Administrative & support | 2012 |
| RUE Sisters Limited | Health & social care | 2015 |
| Rufaro Healthcare Solutions Ltd | Health & social care | 2026 |
| Rufta Properties Ltd | Real estate | 2025 |
| Rufus and Eyre Ltd | Real estate | 2024 |
| RUG and Carpet Wash Ltd | Administrative & support | 2025 |
| Rugshop (Yorkshire) Limited | Wholesale & retail | 2013 |
| RUH Associates Limited | Professional & scientific | 2015 |
| Ruian Creative Ltd | Professional & scientific | 2025 |
| Ruian Media Ltd | Professional & scientific | 2025 |
| Ruian Trading Ltd | Wholesale & retail | 2025 |
| Ruian Vision Ltd | Wholesale & retail | 2025 |
| Ruianwan Trading Limited | Wholesale & retail | 2025 |
| Rukhshaana Estates Ltd | Real estate | 2017 |
| Rukhshaana Properties Ltd | Construction | 2018 |
| Rukuru Limited | Wholesale & retail | 2025 |
| Rumel Properties Ltd | Real estate | 2025 |
| Rumex International Ltd | Wholesale & retail | 2009 |
| Rumi NAZ Limited | Real estate | 2025 |
| Run 71 Ltd | Information & communication | 2012 |
| Run at IT Shouting Productions Ltd | Information & communication | 2014 |
| Run Digital Creative Limited | Administrative & support | 2014 |
| Run Happy Ltd | Wholesale & retail | 2024 |
| Rundleautomotive Ltd | Wholesale & retail | 2026 |
| Running Feral Ltd | Hospitality | 2024 |
| Running on Plants Ltd | Other services | 2022 |
| Runsmooth Renovations & Renewable Energy Limited | Construction | 2025 |
| Ruqaiya Ltd | Transport & logistics | 2022 |
| Rush Barber Ltd | Other services | 2024 |
| Rushleigh Court Limited | Households | 2021 |
| Rusling Estates Ltd | Real estate | 2021 |
| Rusling Investments Limited | Construction | 1971 |
| Rusnorstain Limited | Manufacturing | 2025 |
| Russell Chatterton Limited | Wholesale & retail | 2003 |
| Russell Clothing Ltd | Wholesale & retail | 2019 |
| Russell O'Neill Limited | Construction | 2003 |
| Russell Porter Properties Ltd | Real estate | 2025 |
| Russell Thompson Consulting Limited | Administrative & support | 2013 |
| Russell Wilkinson Ltd | Construction | 2026 |
| Russell's Bicycle Shed Limited | Wholesale & retail | 2016 |
| Russell-Hutton Ltd | Manufacturing | 2004 |
| Russo Holdings Limited | Real estate | 2023 |
| Rustic Computers Limited | Other services | 1997 |
| Rustlings Consulting Ltd | Professional & scientific | 2023 |
| Rustlings Lawn Tennis Club Limited | Arts & recreation | 2023 |
| Ruston Hornsby Ltd | Administrative & support | 2023 |
| Ruth Pearson Training Limited | Professional & scientific | 2010 |
| Ruth Shaw Consulting Ltd | Professional & scientific | 2018 |
| Ruth Square Management Company Limited | Households | 2023 |
| Rutland Body Shop Limited | Wholesale & retail | 2026 |
| Rutland Car Sales Limited | Wholesale & retail | 2025 |
| Rutland Cutlery Works Ltd | Real estate | 2018 |
| Rutland Direct Motor Ltd | Wholesale & retail | 2025 |
| Rutland Heights Ltd | Real estate | 2025 |
| Rutland Mews Flats Limited | Real estate | 2002 |
| Rutland Mews Limited | Construction | 2001 |
| Rutland Park Developments Limited | Construction | 2015 |
| Rutland Park Management Co Limited | Administrative & support | 2017 |
| Rutland Properties (Sheffield) Limited | Real estate | 2017 |
| Rutland Road Trading Limited | Real estate | 2020 |
| Rutland Sandwich Shop Limited | Hospitality | 2025 |
| Rutland Way Partners Limited | Real estate | 2018 |
| Rutledge (John Street) Limited | Real estate | 2006 |
| Rutledge (Neepsend Triangle) Limited | Real estate | 2006 |
| Rutledge (Onslow) Trading Limited | Construction | 2010 |
| Rutynski Properties Ltd | Real estate | 2023 |
| RUV ENT Ltd | Health & social care | 2024 |