| QH Tolleshunt D'Arcy Limited | Hospitality | 2026 |
| QL Ltd | Extraterritorial | 2009 |
| QO Ltd | Extraterritorial | 2010 |
| QQ Limited | Extraterritorial | 2014 |
| QT Ltd | Extraterritorial | 2008 |
| QU Limited | Extraterritorial | 2014 |
| Quarry House Consulting Limited | Information & communication | 2013 |
| Quarterway Commercial Ltd | Real estate | 2023 |
| Quarterway Residential Ltd | Real estate | 2023 |
| QUE Onda Coffee Ltd | Wholesale & retail | 2022 |
| Quilliam Press Ltd | Information & communication | 1988 |
| QURE8 Ltd | Information & communication | 2019 |
| QW Limited | Extraterritorial | 2008 |
| R & a Holdings (Cambridge) Limited | Administrative & support | 2008 |
| R & R Haulage Limited | Transport & logistics | 2008 |
| R House Geophysical Ltd | Professional & scientific | 2026 |
| R Hughes Plumbing & Heating Limited | Construction | 2016 |
| R I Arnold Ltd | Professional & scientific | 2012 |
| R J Datson Limited | Manufacturing | 2014 |
| R N Cansdale & Sons Ltd | Transport & logistics | 2014 |
| R Nevel Painting & Decorating Ltd | Construction | 2018 |
| R Potato Limited | Hospitality | 2012 |
| R&R Leisure Events Ltd | Hospitality | 2022 |
| R-Gazas Ltd | Transport & logistics | 2023 |
| R. Nussey & Co. Limited | Professional & scientific | 1978 |
| R.G. Boyce Limited | Agriculture & fishing | 1973 |
| RAB Havlin Limited | Arts & recreation | 2020 |
| Rabbah Bloodstock Limited | Agriculture & fishing | 1981 |
| RACE4COVER Limited | Professional & scientific | 2008 |
| Racehorse Trader Online Limited | Other services | 2022 |
| Rachel Furze Design Limited | Professional & scientific | 2011 |
| RAE Guest Racing Limited | Other services | 2002 |
| Rams Paker Limited | Hospitality | 2024 |
| Ramsey Motorhomes Ltd | Wholesale & retail | 2025 |
| Rancho Temescal Bloodstock Limited | Agriculture & fishing | 2025 |
| Ranger Engineering and Developments Limited | Real estate | 1960 |
| Rani Estates Limited | Real estate | 2025 |
| Rapido Racing Limited | Transport & logistics | 2015 |
| Ravenward Small Projects Ltd | Construction | 2011 |
| Raziel Designs Ltd | Wholesale & retail | 2023 |
| RB Ltd | Extraterritorial | 2023 |
| RBJ Property Estates & Development Ltd | Professional & scientific | 2022 |
| RD Ltd | Extraterritorial | 2009 |
| Rd&B (Exning) Ltd | Real estate | 2020 |
| RDC Groundworks & Construction Ltd | Construction | 2019 |
| Rebecca Taylor Aesthetics Limited | Health & social care | 2017 |
| Rebuild Home Improvements Limited | Construction | 2017 |
| Red House Stables Limited | Arts & recreation | 2015 |
| Red Leaf Property Ltd | Real estate | 2026 |
| Red Lion Latchingdon Ltd | Hospitality | 2022 |
| Red Papillon Ltd | Arts & recreation | 2020 |
| Red Robin Activities Ltd | Administrative & support | 2022 |
| Red Toad Commerce Ltd | Wholesale & retail | 2023 |
| Red Tree Representation Limited | Other services | 2007 |
| Redlocks Locksmiths Ltd | Manufacturing | 2017 |
| Reed Bloodstock and Racing Limited | Agriculture & fishing | 2020 |
| Reed Design and Build Newmarket Limited | Construction | 2019 |
| Reed Design and Build Suffolk Limited | Construction | 2022 |
| Reed Property Developments Limited | Real estate | 2018 |
| Reed Property Managment Limited | Real estate | 2018 |
| Refined Bottisham Limited | Real estate | 2023 |
| Refined Commercial Interiors Ltd | Administrative & support | 2017 |
| Regal Trading (EA) Limited | Wholesale & retail | 2023 |
| Regency Cakes Limited | Manufacturing | 2016 |
| Regent Place Group Limited | Hospitality | 2017 |
| Reliance Health and Care Services - Suffolk Ltd | Health & social care | 2024 |
| Relocate Cambridge Ltd | Real estate | 2005 |
| Remy Nails Newmarket Ltd | Other services | 2026 |
| Remy Nails TN Ltd | Other services | 2024 |
| Rent Right (London) Limited | Transport & logistics | 2014 |
| Repairbrook Limited | Real estate | 2001 |
| Reply Track Repairs Limited | Manufacturing | 2025 |
| Reply Tracks Limited | Manufacturing | 2025 |
| Research and Development Hub Ltd | Professional & scientific | 2022 |
| Residents Road Management Limited | Households | 2006 |
| Resources in the Community Limited | Administrative & support | 2003 |
| RFP & Sons Ltd | Real estate | 2024 |
| RGA Homes Limited | Construction | 2023 |
| Richard Beadle Livestock Limited | Extraterritorial | 1989 |
| Richard Frisby Bloodstock Ltd | Professional & scientific | 2001 |
| Richard Furze Electrical Ltd | Construction | 2017 |
| Richard Venn Bloodstock Ltd | Arts & recreation | 2007 |
| Richer Food Limited | Manufacturing | 2020 |
| Richer Spirits Ltd | Wholesale & retail | 2023 |
| Richmond Lonsdale Limited | Professional & scientific | 1967 |
| Richmond New Zealand Limited | Professional & scientific | 1991 |
| Ridgeback Construction & Developments Ltd | Construction | 2019 |
| Ridgemount Shipping Ltd | Transport & logistics | 1991 |
| Rikki-Tikki-Tavi Ltd | Financial services | 2023 |
| Ring Communications (U.K.) Limited | Information & communication | 1988 |
| Ringtrack Ltd | Financial services | 1997 |
| Rising Sun Bloodstock Limited | Agriculture & fishing | 2017 |
| Riverlark Limited | Professional & scientific | 2004 |
| Riverside Walk (Moulton) Management Company Limited | Households | 2009 |
| Rizdirect Limited | Wholesale & retail | 2024 |
| RJ Ltd | Extraterritorial | 2009 |
| RJ Taylor Farms Ltd | Agriculture & fishing | 2016 |
| RJB Industrial Services Ltd | Manufacturing | 2025 |
| Rjpl Import Ltd | Administrative & support | 2026 |
| RL Trans Ltd | Administrative & support | 2017 |