| Raglan Quizco Limited | Information & communication | 2024 |
| Ragswet Ltd | Real estate | 2025 |
| RAH Building Ltd | Construction | 2015 |
| Rahan Transporting Ltd | Transport & logistics | 2021 |
| Rahma Emergency AID CIC | Construction | 2025 |
| Raif Ltd | Real estate | 2024 |
| Rainbow Business Finance Limited | Administrative & support | 2019 |
| Rainbow Cleaning Ltd | Administrative & support | 2021 |
| Rainbow International Imp&Exp Limited | Extraterritorial | 2019 |
| Rainbow Rocket Limited | Arts & recreation | 2017 |
| Rainfast Ltd | Construction | 2016 |
| RAINIE1955 Ltd | Professional & scientific | 2016 |
| Rainsford Financial Planning Ltd | Professional & scientific | 2016 |
| Rainsun International Ltd | Wholesale & retail | 2022 |
| RAK Consulting Ltd | Professional & scientific | 2024 |
| Rakiza Ventures Limited | Financial services | 2025 |
| Rakon UK Holdings Limited | Professional & scientific | 2006 |
| Rakon UK Limited | Professional & scientific | 2004 |
| Rakun Ltd | Wholesale & retail | 2023 |
| Rallisart Limited | Arts & recreation | 2016 |
| Rally Precision Ltd | Wholesale & retail | 2023 |
| Rallycart Limited | Hospitality | 2018 |
| Ralph Design Limited | Professional & scientific | 2010 |
| Rals Retail Ltd | Wholesale & retail | 2025 |
| Raly Composites Ltd | Manufacturing | 2024 |
| RAM Multi Services Ltd | Hospitality | 2025 |
| Rama Global Foods Ltd | Wholesale & retail | 2024 |
| Ramatol Ltd | Financial services | 2024 |
| Ramdehi Groups Limited | Information & communication | 2024 |
| Ramondou Slade Ltd | Professional & scientific | 2025 |
| Rampton Car Breakers Limited | Water & waste | 2013 |
| Rampton Development Ltd | Construction | 2024 |
| Rampton Inns Limited | Hospitality | 2022 |
| Ramrous Holdings Ltd | Real estate | 2018 |
| Ramsay Court Management Company Limited | Real estate | 2006 |
| Ramzan Racehorse Consultancy Ltd | Professional & scientific | 2025 |
| RAN TON Sound Limited | Manufacturing | 2023 |
| Rand Europe Community Interest Company | Professional & scientific | 1992 |
| Rand Europe UK Ltd | Professional & scientific | 2000 |
| Randomnine Limited | Information & communication | 2012 |
| Randswood Farm LP | | 2010 |
| Rane Duncan Consulting Ltd | Professional & scientific | 2024 |
| Ranebeau Limited | Information & communication | 1996 |
| Rankine Consultancy Limited | Administrative & support | 2023 |
| Rankine Limited | Real estate | 2014 |
| Ranplan Holdings Limited | Information & communication | 2014 |
| Ranplan Wireless Network Design Ltd | Information & communication | 2006 |
| RAO Vignault Consulting Limited | Professional & scientific | 2017 |
| Raokul Ltd | Real estate | 2024 |
| Raphael’S Motor Trading Ltd | Wholesale & retail | 2025 |
| Rapid Delivery Ltd | Wholesale & retail | 2023 |
| Rapid Solutions (International) Limited | Administrative & support | 2014 |
| Rapidx BIO Ltd | Manufacturing | 2022 |
| Rapiere Software Limited | Information & communication | 2013 |
| Raptor Bidco Limited | Financial services | 2021 |
| Raptor Entertainment Ltd | Wholesale & retail | 2018 |
| Raptor Midco 1 Limited | Financial services | 2021 |
| Raptor Midco 2 Limited | Financial services | 2021 |
| Raptor Topco Limited | Financial services | 2021 |
| Rapunzel Rocks Limited | Other services | 2020 |
| Rarico Ltd | Information & communication | 2026 |
| Rarlon International Media Co., Ltd. | Wholesale & retail | 2025 |
| Rasa Housing Ltd | Real estate | 2021 |
| Rasoi Cambridge Limited | Hospitality | 2021 |
| Rason Assets Management Limited | Real estate | 2022 |
| Raspado Consulting Services Ltd | Information & communication | 2021 |
| Raspberry PI Foundation | Professional & scientific | 2008 |
| Raspberry PI Holdings PLC | Professional & scientific | 2024 |
| Raspberry PI Ltd | Professional & scientific | 2012 |
| Raspberry PI MID Co Limited | Professional & scientific | 2021 |
| Raumkunst Limited | Real estate | 2022 |
| Rave'Ing INK Limited | Arts & recreation | 2019 |
| Raven Red Productions Ltd | Information & communication | 2019 |
| Ravenbrook Limited | Information & communication | 1997 |
| Ravensworth Gardens Residents' Association Limited | Real estate | 1999 |
| Ravson Estates Ltd | Construction | 2025 |
| Ravson Group Ltd | Financial services | 2025 |
| Ravson Interiors Ltd | Manufacturing | 2025 |
| Rawal Orthopaedics Ltd | Health & social care | 2021 |
| Raxandax Partners LLP | | 2016 |
| Raybin Homewares Co., Ltd | Wholesale & retail | 2024 |
| Rayfield Allied Ltd | Arts & recreation | 2010 |
| Rayfield Property Limited | Real estate | 2018 |
| Raymarc Investments Limited | Real estate | 2021 |
| Raymark Consulting Limited | Information & communication | 2015 |
| Rayment's Garage Limited | Wholesale & retail | 2007 |
| Raymond Road Estate Limited | Households | 1990 |
| Raynhams Management Company Limited | Households | 1999 |
| Rayong International Investment Limited | Mining & quarrying | 2023 |
| Rayren Ltd | Administrative & support | 2025 |
| Razion Cleaning Ltd | Administrative & support | 2025 |
| Razvanaerostructure Ltd | Manufacturing | 2025 |
| RAZVANNAN1990 Ltd | Manufacturing | 2023 |
| RB Associates Cambridge Limited | Professional & scientific | 2020 |
| RB Financial Decisions Ltd | Financial services | 2025 |
| RB Medical and Training Ltd | Education | 2025 |
| RB Prestige Motors Ltd | Wholesale & retail | 2025 |
| RBAR3 Limited | Administrative & support | 2014 |
| RBB Flex Limited | Transport & logistics | 2025 |
| RBT FLY Ltd | Manufacturing | 2024 |