| RKO Construction Ltd | Professional & scientific | 2025 |
| RKS Property Investments Ltd | Real estate | 2026 |
| RL Legal Consultancy Limited | Professional & scientific | 2017 |
| RLR Enterprises Ltd | Wholesale & retail | 2020 |
| RLS Print and Design Ltd | Information & communication | 2016 |
| RM Beauty & Aesthetics Ltd | Other services | 2022 |
| RM Cars Northampton Ltd | Transport & logistics | 2025 |
| RM Moving Ltd | Transport & logistics | 2026 |
| RM Utilities Limited | Construction | 2007 |
| Rm&Truck Ltd | Transport & logistics | 2025 |
| RMB Commercials Ltd | Wholesale & retail | 2020 |
| RMB Lighting Limited | Information & communication | 2014 |
| RMB Pipework Services Ltd | Construction | 2018 |
| RMC Builders Ltd | Construction | 1976 |
| RMD Surfacing Ltd | Construction | 2020 |
| RMF Auto Electrical Limited | Wholesale & retail | 2016 |
| RMG Developments Ltd | Construction | 2023 |
| RML Facilities Services Ltd | Administrative & support | 2012 |
| RMM Brickwork Limited | Construction | 2025 |
| Rmnl Limited | Transport & logistics | 2020 |
| RMR Control & Automation Limited | Manufacturing | 2003 |
| RMS Stone Ltd | Wholesale & retail | 2020 |
| RMV Estate Limited | Real estate | 2023 |
| RNA Logistics Ltd | Transport & logistics | 2025 |
| RNB Meat Store Limited | Wholesale & retail | 2025 |
| RNB Plumbing Ltd | Construction | 2025 |
| RNR Care Ltd | Health & social care | 2020 |
| RNR Property Management Limited | Real estate | 2025 |
| Rnst Ltd | Health & social care | 2020 |
| RO Meat Factory Ltd | Manufacturing | 2024 |
| Road and Rally Discount Accessories Limited | Wholesale & retail | 1981 |
| Road and Sport Developments Limited | Wholesale & retail | 2007 |
| Road Expert Driving School Ltd | Education | 2024 |
| Road Mate Lorry Ltd | Transport & logistics | 2025 |
| Road River Freight Limited | Transport & logistics | 2002 |
| Road Runner Express Limited | Wholesale & retail | 2015 |
| Roade Healthcare Limited | Wholesale & retail | 2019 |
| Roade Main Garage Ltd | Wholesale & retail | 2010 |
| Roade Rascals Limited | Health & social care | 2014 |
| Roadgaz Doncaster Ltd | Construction | 2015 |
| Roan Trans Ltd | Transport & logistics | 2022 |
| Roar Digital Services Ltd | Information & communication | 2018 |
| Roar Performance Limited | Wholesale & retail | 2011 |
| Roar Ventures Limited | Real estate | 2018 |
| ROB Rowe Project Solutions Ltd | Professional & scientific | 2025 |
| ROB White Mentoring C.I.C. | Health & social care | 2023 |
| ROB White Mentoring Services Ltd | Health & social care | 2023 |
| Robbie Fitz Ltd | Arts & recreation | 2026 |
| Robbiesday Ltd | Arts & recreation | 2026 |
| Robbins Properties Limited | Real estate | 2022 |
| Robe UK Ltd | Wholesale & retail | 2003 |
| Robert 1 Ltd | Transport & logistics | 2022 |
| Robert Auto Services Ltd | Wholesale & retail | 2018 |
| Robert Bruce Associates Limited | Financial services | 2011 |
| Robert Bruce Limited | Financial services | 2018 |
| Robert Bruce Private Clients a Limited | Financial services | 2019 |
| Robert Bruce Private Clients B Limited | Financial services | 2019 |
| Robert Bruce Private Clients Limited | Financial services | 2019 |
| Robert Butler Financial Associates Limited | Financial services | 2024 |
| Robert Cope BDS Limited | Health & social care | 2008 |
| Robert J Kennedy Consulting Limited | Professional & scientific | 2017 |
| Robertson Bell EOT Limited | Administrative & support | 2022 |
| Robertson Bell Ltd | Administrative & support | 2007 |
| Robertson New Homes Ltd | Construction | 2017 |
| Robertson Software Limited | Information & communication | 2014 |
| Robin Events Ltd | Hospitality | 2025 |
| Robins & Co Limited | Extraterritorial | 2013 |
| Robins Transport Services Ltd | Transport & logistics | 2019 |
| Robinson Builders Limited | Construction | 2018 |
| Robinson Retail Shop Ltd | Wholesale & retail | 2025 |
| Robinson's Letting Solutions Limited | Real estate | 2025 |
| Robleeds Ltd | Wholesale & retail | 2024 |
| Robson Delivery Limited | Transport & logistics | 2023 |
| Roby Trading Ltd | Transport & logistics | 2016 |
| ROC Ridge Limited | Construction | 2025 |
| Rocas Consulting Ltd | Administrative & support | 2019 |
| Roche Access Scaffolding Limited | Construction | 2025 |
| Rochmills (Holdings) Limited | Financial services | 2016 |
| Rochmills Developments Ltd | Real estate | 2015 |
| Rochmills Limited | Real estate | 2017 |
| Rochmills Property Ltd | Real estate | 2017 |
| Rock Bottom Northampton Ltd | Wholesale & retail | 2023 |
| Rock Cottage Limited | Real estate | 2022 |
| Rock Roofing Products Limited | Manufacturing | 2013 |
| Rockbottom Cars Ltd | Wholesale & retail | 2014 |
| Rocketstar Games Ltd | Information & communication | 2024 |
| Rockingham Manufacturing Limited | Manufacturing | 2003 |
| Rockit Children's Boutique Ltd | Manufacturing | 2019 |
| Rockviewcare Limited | Health & social care | 2014 |
| ROD Doyle Consultancy Ltd | Education | 2011 |
| Rodericks (Chalfont ST Giles) Limited | Health & social care | 2016 |
| Rodericks (Wales) Limited | Health & social care | 2015 |
| Rodericks Beeston Ltd | Health & social care | 2019 |
| Rodericks Dental Partners Limited | Health & social care | 1923 |
| Rodericks Labs Limited | Health & social care | 2022 |
| Rodericks Mexborough Ltd | Health & social care | 2019 |
| Rodericks Private Limited | Health & social care | 2016 |
| Rodrigues Carvalho Ltd | Hospitality | 2025 |
| ROE Road Management Company Limited | Households | 2000 |
| Roeslein & Associates, Ltd | Professional & scientific | 2007 |