| Reid Plan Limited | Professional & scientific | 2018 |
| Relaxation & Leisure Limited | Administrative & support | 2018 |
| Reliable Roofing Ltd | Construction | 2015 |
| Reliance Worldwide Corporation Holdings (UK) Limited | Financial services | 1943 |
| Reliance Worldwide Distribution (Europe) Limited | Wholesale & retail | 2021 |
| Reliance Worldwide Finance Limited | Financial services | 2018 |
| Reliance Worldwide Holdings (UK) Limited | Wholesale & retail | 2016 |
| Remarkable Children Limited | Health & social care | 2020 |
| Renaed Limited | Health & social care | 2023 |
| Renaissance Trans Ltd | Transport & logistics | 2023 |
| Renoir Homes Ltd | Real estate | 2022 |
| Rentalcar UK Limited | Administrative & support | 2003 |
| Rentaloasis Ltd | Real estate | 2023 |
| Resinroos Ltd | Wholesale & retail | 2024 |
| Revision UK GP Management Limited | Real estate | 2024 |
| Revision UK Holdings Limited | Financial services | 2024 |
| Revolutions Info Limited | Information & communication | 2008 |
| Rewaj Ltd | Wholesale & retail | 2024 |
| Reweem International Ltd | Information & communication | 2025 |
| REX Charles Legal Ltd | Households | 2023 |
| REX Charles Ltd | Administrative & support | 2025 |
| RF & JAG Ltd | Transport & logistics | 2024 |
| RFT Comms Ltd | Information & communication | 2018 |
| RHM Building Infrastructure Services Ltd | Professional & scientific | 2014 |
| Ribbon Acquisition Limited | Financial services | 2005 |
| Ribbon Basildon Limited | Hospitality | 2017 |
| Ribbon Bidco Limited | Financial services | 2015 |
| Ribbon Birmingham Limited | Hospitality | 2017 |
| Ribbon Brent Cross Limited | Hospitality | 2017 |
| Ribbon Brentwood Limited | Hospitality | 2017 |
| Ribbon Bristol Limited | Hospitality | 2017 |
| Ribbon Cambridge Limited | Hospitality | 2017 |
| Ribbon Cardiff Limited | Hospitality | 2017 |
| Ribbon Edinburgh Limited | Hospitality | 2017 |
| Ribbon Glasgow Airport Limited | Hospitality | 2017 |
| Ribbon Guildford Limited | Hospitality | 2017 |
| Ribbon Heathrow Limited | Hospitality | 2017 |
| Ribbon Heathrow M4 J4 Limited | Hospitality | 2017 |
| Ribbon Holdco Limited | Hospitality | 2015 |
| Ribbon Hotels Management Limited | Hospitality | 2015 |
| Ribbon Maidenhead Limited | Hospitality | 2017 |
| Ribbon Manchester Airport Limited | Hospitality | 2017 |
| Ribbon Mezzco Limited | Hospitality | 2015 |
| Ribbon Midco Limited | Financial services | 2015 |
| Ribbon Milton Keynes Limited | Hospitality | 2017 |
| Ribbon Oxford Limited | Hospitality | 2017 |
| Ribbon Regents Park Limited | Hospitality | 2017 |
| Ribbon Sutton Limited | Hospitality | 2017 |
| Richel Ltd | Health & social care | 2024 |
| Richox Ltd | Professional & scientific | 2015 |
| Ride Properties Ltd | Construction | 2024 |
| Riders Point Ltd | Wholesale & retail | 2024 |
| Ridley Industries Limited | Information & communication | 2010 |
| Right Choice Tree Surgeons Ltd Limited | Arts & recreation | 2025 |
| Rignall Garage Ltd | Wholesale & retail | 2023 |
| Rigscare Ltd | Health & social care | 2026 |
| Rimell Estates Ltd | Hospitality | 2025 |
| Rions Car Care Ltd | Wholesale & retail | 2024 |
| Rise & Achieve CIC | Hospitality | 2026 |
| Ristoiu Construction Ltd | Manufacturing | 2026 |
| Ritual Mandaps Ltd | Hospitality | 2021 |
| Ritual Thread London Ltd | Wholesale & retail | 2020 |
| Riwald Limited | Wholesale & retail | 2009 |
| Riyansh Construction Ltd | Construction | 2024 |
| RJC Electrical & Construction Ltd | Construction | 2025 |
| Rjdhada Estates Ltd | Real estate | 2025 |
| RKM Legacy Investments Ltd | Real estate | 2021 |
| Rmdoster Ltd | Administrative & support | 2021 |
| RMT Tyres Ltd | Wholesale & retail | 2002 |
| RMW Residences Ltd | Real estate | 2026 |
| RNS Investments and Holdings Ltd | Real estate | 2016 |
| Robert Fastyn Ltd | Construction | 2023 |
| Robinhood Roofing Ltd | Construction | 2025 |
| Robot Planet Limited | Wholesale & retail | 2023 |
| Rockmere Finance Ltd | Financial services | 2025 |
| ROD Chisholm Ltd | Information & communication | 2015 |
| Roda House Ltd | Manufacturing | 2025 |
| Rokka Build Limited | Construction | 2025 |
| Romfast Transport Ltd | Transport & logistics | 2024 |
| Romwork Limited | Construction | 2009 |
| Ronak Hair & Beauty Salon Ltd | Other services | 2026 |
| Ronav Software Ltd | Information & communication | 2020 |
| Ronay Limited | Wholesale & retail | 2025 |
| Rononiti Ltd | Professional & scientific | 2019 |
| Roof Care (London) Ltd | Construction | 2018 |
| Ross Auto Engineering Limited | Health & social care | 1949 |
| Roua Market Ltd | Wholesale & retail | 2021 |
| Round the Clock Airport Transfer Ltd | Transport & logistics | 2024 |
| Royale Crown Pizza Ltd | Hospitality | 2023 |
| Royale Spartan Ltd | Real estate | 2019 |
| Rozana Foods Limited | Agriculture & fishing | 2019 |
| RRG Systems Limited | Wholesale & retail | 2025 |
| RS Dhillon Ltd | Transport & logistics | 2024 |
| RSK Netventure Ltd | Professional & scientific | 2023 |
| RSP Trade Ltd | Wholesale & retail | 2026 |
| RT Properties and Investments Ltd | Real estate | 2024 |
| Rubystone Estates Limited | Real estate | 2023 |
| Ruijie Networks (UK) Limited | Wholesale & retail | 2023 |
| Rumo Restaurant Ltd | Hospitality | 2025 |
| Ruzbuild Ltd | Construction | 2024 |