| R.M.N 1-2-1 Care Ltd | Health & social care | 2012 |
| R.Smith & Co.,Limited | Information & communication | 1900 |
| R.W.Beaty(Farms)Limited | Agriculture & fishing | 1971 |
| R2 Building Services Ltd | Construction | 2020 |
| R4CARE Limited | Health & social care | 2020 |
| R8 Scaffolding Limited | Construction | 2023 |
| Rablaid Investments Limited | Professional & scientific | 2006 |
| Race Harborough Ltd | Arts & recreation | 2014 |
| Race Transport UK to EU Limited | Wholesale & retail | 2022 |
| Rack Experts Limited | Professional & scientific | 2022 |
| Radhika P Services Limited | Health & social care | 2019 |
| Radulian Construction Ltd | Construction | 2019 |
| Radzikat Ltd | Wholesale & retail | 2023 |
| Radziwon Ltd | Wholesale & retail | 2026 |
| RAF Joinery Venture Ltd | Construction | 2023 |
| RAF77 Ltd | Transport & logistics | 2015 |
| Raffenday Ltd | Manufacturing | 1987 |
| Rags Installs Ltd | Construction | 2025 |
| Rahman Indian Catering Ltd | Hospitality | 2026 |
| Railnews Limited | Information & communication | 1996 |
| Railway Modelling Experts Limited | Arts & recreation | 2018 |
| Rainbow Heritage Project Services Limited | Financial services | 2021 |
| Rainworth Energy Limited | Energy | 2015 |
| RAJ Mini Market Limited | Wholesale & retail | 2013 |
| RAK Design (UK) Limited | Administrative & support | 2000 |
| Raktronics Limited | Information & communication | 2013 |
| RAM Grocery Limited | Wholesale & retail | 2026 |
| Ramona Services Ltd. | Wholesale & retail | 2014 |
| Ramone Incorporated Ltd | Wholesale & retail | 2023 |
| Randomshiv Limited | Manufacturing | 2025 |
| Raoul T&A Limited | Transport & logistics | 2017 |
| Rapha Care Group Ltd | Administrative & support | 2023 |
| Rapid Response Distribution Ltd | Transport & logistics | 2025 |
| Rapid Response Ltd | Transport & logistics | 2024 |
| Rapier Motors Limited | Other services | 2005 |
| RAS Engineering Ltd | Transport & logistics | 2017 |
| Rathee Limited | Information & communication | 2024 |
| Ratnaafin Business Solutions Ltd | Professional & scientific | 2018 |
| Ratnaafin Global Holdings Limited | Financial services | 2019 |
| Rauls Design Limited | Wholesale & retail | 2022 |
| Raunds Delight Limited | Hospitality | 2025 |
| Raunds Electrical Limited | Construction | 1973 |
| Raunds Grab Hire Ltd | Transport & logistics | 2019 |
| Raunds Town Football & Social Club CIC | Other services | 2026 |
| Raunds Tyres Ltd | Wholesale & retail | 2022 |
| Ravanaa Ltd | Wholesale & retail | 2024 |
| Ravica Ltd | Health & social care | 2022 |
| RAY EKO Ltd | Professional & scientific | 2016 |
| RAY RR Logistics Ltd | Transport & logistics | 2025 |
| Raymasy Ltd | Health & social care | 2022 |
| Razvan Marian Trans Ltd | Transport & logistics | 2025 |
| RC Motorcycles Ltd | Wholesale & retail | 2026 |
| RC23 Plumbing & Heating Ltd | Construction | 2025 |
| Rcabusinessmanagement Ltd | Hospitality | 2026 |
| Rcstelecom Ltd | Information & communication | 2025 |
| RDM Racetech Ltd | Other services | 2022 |
| Real Bar Ltd | Hospitality | 2026 |
| Rebecca the Baker Ltd | Manufacturing | 2025 |
| Rebranding Safety Ltd | Information & communication | 2021 |
| Recruiteum Ltd | Administrative & support | 2025 |
| Red Berry Trading Limited | Professional & scientific | 2012 |
| Red Eagles FC Ltd | Arts & recreation | 2018 |
| Red Lotus Consultancy Limited | Professional & scientific | 2025 |
| Red Pearl Consulting Ltd | Professional & scientific | 2024 |
| Red Pearl Creations Ltd | Other services | 2013 |
| Red Sky Renovations Limited | Construction | 2020 |
| RED17 Ltd | Professional & scientific | 2006 |
| Redbank Mews Management Company Limited | Households | 2016 |
| Redeye Supplies Ltd | Wholesale & retail | 2025 |
| Redlane Sites Limited | Professional & scientific | 1964 |
| Redwell Court Limited | Households | 2005 |
| Redwell Decorations Limited | Construction | 2010 |
| Redwell Housing Limited | Real estate | 2024 |
| Redwing Aviation Ltd | Manufacturing | 2020 |
| Reece Plumbing and Heating Limited | Construction | 2023 |
| Refocus Ltd | Education | 2020 |
| Regal Heat Limited | Construction | 2019 |
| Regal Reflection Cleaners Ltd | Administrative & support | 2024 |
| Regal Securities Limited | Hospitality | 2025 |
| Regent House Property Limited | Real estate | 2020 |
| Regent Park Management Company Limited | Other services | 2001 |
| Regent Park Offices Management Company Limited | Real estate | 2012 |
| Regent Street (Kettering) Management Company Limited | Real estate | 2006 |
| Rehman Group Ltd | Wholesale & retail | 2020 |
| Rehoboth International Limited | Wholesale & retail | 2015 |
| Rehoboth IT Services Ltd | Information & communication | 2014 |
| Reilly Trade + Classic Ltd | Wholesale & retail | 2020 |
| Reis BBQ Ltd | Hospitality | 2024 |
| Rejuv Aesthetics Limited | Wholesale & retail | 2022 |
| Remada Blinds Solution Ltd | Construction | 2024 |
| Remati Ltd | Transport & logistics | 2024 |
| Renatus London UK Ltd | Wholesale & retail | 2025 |
| Renner Coatings UK Limited | Manufacturing | 2007 |
| Renrose Investments Ltd | Households | 2025 |
| Renutec Europe Limited | Other services | 2014 |
| Rescare Northampton Ltd | Health & social care | 2020 |
| Resolve Coaching and Development Ltd | Health & social care | 2020 |
| Restoration Services Ltd | Administrative & support | 2015 |
| Restore and Renew Recovery LLP | | 2026 |
| Retail Business Solutions Limited | Other services | 2015 |