| R-B Maintenance & Cleaning Service Ltd | Construction | 2024 |
| Rainbowcreative Ltd | Information & communication | 2020 |
| Rainmaker Media Services Limited | Professional & scientific | 2008 |
| Ramshaw-Watkins Limited | Professional & scientific | 2003 |
| Rare P Parts Ltd | Wholesale & retail | 2024 |
| Ravensworth Agencies Ltd | Real estate | 2012 |
| RAY Lodge Mews Management Company Limited | Households | 2024 |
| Rcmj Consultancy Ltd | Professional & scientific | 2024 |
| RDB Services Ltd | Professional & scientific | 2019 |
| RDC Communications Limited | Information & communication | 2000 |
| RDL Coaching Ltd | Arts & recreation | 2024 |
| Readers Court Management Limited | Households | 1998 |
| Rebar Consulting Ltd | Professional & scientific | 2025 |
| Red Bird Marketing Limited | Professional & scientific | 2012 |
| Red Civils (Oxford) Ltd | Construction | 2024 |
| Red COW Cider Limited | Wholesale & retail | 2020 |
| Red Eight Capital Limited | Financial services | 2003 |
| Red Group (Oxford) Ltd | Construction | 2024 |
| Red Kite Land Company Limited | Professional & scientific | 1998 |
| Red Metal Works Ltd | Manufacturing | 2018 |
| Redesdale Arms Limited | Hospitality | 1999 |
| Redesdale Holdings Ltd | Professional & scientific | 2015 |
| Redkite Solutions Limited | Information & communication | 1999 |
| Redstone Media Ltd | Professional & scientific | 2025 |
| Reduced Overheads Limited | Administrative & support | 2015 |
| Refind Coaching Ltd | Professional & scientific | 2026 |
| Refinery Direct Ltd | Wholesale & retail | 2000 |
| Regatta Automotive Services Ltd | Wholesale & retail | 2021 |
| Regatta Car Hire Ltd | Administrative & support | 2020 |
| Regatta Commercial Property Limited | Real estate | 2024 |
| Regatta Strategic Partners Limited | Professional & scientific | 2021 |
| Regenerativ Ltd | Information & communication | 2023 |
| Regulatory Consultancy Services LLP | | 2008 |
| Remenham Club,Limited.(The) | Hospitality | 1911 |
| Remenham Consulting Limited | Professional & scientific | 2014 |
| Remo Consulting Limited | Information & communication | 2020 |
| REN Holdings Limited | Information & communication | 2015 |
| Renaissance Leadership International Limited | Administrative & support | 2004 |
| Renaissance Leadership US Limited | Administrative & support | 2020 |
| Renown Pharma Limited | Financial services | 2015 |
| Rent Bell Tents Ltd | Hospitality | 2021 |
| Replenished.Ukservices Limited | Wholesale & retail | 2025 |
| Resolve Electrical and Mechanical Services Ltd | Construction | 2025 |
| Retailise Limited | Wholesale & retail | 2023 |
| Rethrodent Limited | Health & social care | 2017 |
| Revival Revolution Ltd | Information & communication | 2021 |
| Revive Electrical Solutions Ltd | Construction | 2017 |
| Reynolds Court RTM Company Limited | Households | 2022 |
| Rich Plastering Ltd | Construction | 2025 |
| Richardson Paintings Limited | Wholesale & retail | 2005 |
| RIDE25 Limited | Administrative & support | 2014 |
| Ridgeback Services Limited | Professional & scientific | 2024 |
| Ridgebank Management (Slough) Limited | Households | 1996 |
| RIG Cameras Ltd | Information & communication | 2023 |
| Rigden Studio Ltd | Professional & scientific | 2019 |
| Ringside Executive Solutions Limited | Construction | 2023 |
| Rise Analytics Ltd | Administrative & support | 2022 |
| Riverbank Studios (Worsham) Management Company Limited | Households | 2007 |
| Rivercourt Homes Limited | Households | 1985 |
| Riverside RP Limited | Hospitality | 2014 |
| Riverside Wines Ltd | Wholesale & retail | 2023 |
| Riviera House Boutique Ltd | Wholesale & retail | 2025 |
| Riza Barbers Limited | Other services | 2023 |
| RJ Energy Limited | Professional & scientific | 2007 |
| Rj&Mp Investments and Holdings Limited | Financial services | 2021 |
| Rjalogix Limited | Wholesale & retail | 2018 |
| RJG Media Ltd | Professional & scientific | 2019 |
| RK Consulting & Associates Ltd | Professional & scientific | 2017 |
| Road Rubber Ltd | Wholesale & retail | 2017 |
| Robbie Mills Illustration Ltd | Professional & scientific | 2014 |
| Robe & SON Ltd | Other services | 2023 |
| Robin Hughes and Associates Ltd | Professional & scientific | 2019 |
| Robinson Ranger Property Holdings Limited | Hospitality | 2026 |
| Robinson Sherston Limited | Financial services | 2025 |
| Rock the Boat Clothing Limited | Wholesale & retail | 2003 |
| Rockoptic.Com Ltd | Arts & recreation | 1994 |
| Rocks Technology Limited | Information & communication | 2021 |
| Rockstone Associates Limited | Professional & scientific | 2017 |
| Roger and OUT Limited | Administrative & support | 2008 |
| ROK DEV Ltd | Construction | 2022 |
| Romeril Capital Limited | Information & communication | 2021 |
| Rook Piercing Limited | Wholesale & retail | 2023 |
| Roose Ltd | Professional & scientific | 2021 |
| Rosehill Ventures Limited | Real estate | 2023 |
| Roslee Care Holdings Ltd | Health & social care | 2025 |
| Rotherfield Garth (Henley on Thames) Management Company Limited | Households | 2016 |
| Rotherfield Residential Property Limited | Real estate | 2021 |
| Rougevin Limited | Wholesale & retail | 2022 |
| Rousant Sherwood (Manufacturing) Limited | Manufacturing | 1977 |
| Rowland Hill Court Freehold Limited | Households | 2018 |
| Rowland Hill Court Management Company Limited | Households | 2000 |
| Royal Quarter Management Company Limited | Households | 2002 |
| RPL Investments Ltd | Professional & scientific | 2013 |
| Rubix and Co Properties Limited | Construction | 2025 |
| Rubix Holding Group Limited | Financial services | 2025 |
| Rubix Interiors Limited | Construction | 2017 |
| Rumble Holdings Limited | Information & communication | 2016 |
| Rush Sports Marketing Limited | Professional & scientific | 2010 |
| Russet Limited | Hospitality | 2003 |
| Ruvien Limited | Administrative & support | 2018 |