| Regidius Ltd | Information & communication | 2022 |
| Reign Digital Consulting Ltd | Professional & scientific | 2024 |
| Reilly Property Holdings Ltd | Real estate | 2025 |
| Reis Media Ltd | Professional & scientific | 2022 |
| Relax-Renew Therapy Limited | Other services | 2026 |
| Relevant Five Ltd | Administrative & support | 2024 |
| Remmus Ardingly Ltd | Real estate | 2024 |
| Remmus Build Ltd | Construction | 2022 |
| Remmus Designer Homes Ltd | Real estate | 2015 |
| Remmus Holdings Ltd | Financial services | 2025 |
| Remmus IP Ltd | Real estate | 2024 |
| Remmus Maresfield Ltd | Construction | 2025 |
| Remmus Ventures Ltd | Construction | 2026 |
| Remmus Wintons Ltd | Construction | 2022 |
| Remmus Wisborough Green Ltd | Construction | 2024 |
| Remotelock UK Ltd | Wholesale & retail | 2015 |
| Remove the Dent Limited | Wholesale & retail | 2013 |
| Removere Ltd | Transport & logistics | 2023 |
| REN Properties Plus Limited | Information & communication | 2020 |
| Renavero Ltd | Transport & logistics | 2023 |
| Renewcycle Solutions Ltd | Water & waste | 2021 |
| Renewed Strength Fitness Limited | Arts & recreation | 2026 |
| Renmakesmerch Limited | Wholesale & retail | 2026 |
| Reno JJ Limited | Real estate | 2011 |
| Rent-A-Santa Limited | Arts & recreation | 2024 |
| Rental Bikes Brighton Ltd | Wholesale & retail | 2024 |
| Rental Oriental Limited | Real estate | 2025 |
| Rentmoor Limited | Real estate | 1954 |
| Republic Drinks Ltd | Wholesale & retail | 2023 |
| Republic of Music Limited | Arts & recreation | 2006 |
| Republic of Sync Limited | Arts & recreation | 2014 |
| Reset and Rediscover Ltd | Other services | 2020 |
| Residents' Association 28 Brunswick Place Limited | Hospitality | 1998 |
| Resilia Consulting Limited | Professional & scientific | 2012 |
| Resolute Performance Ltd | Arts & recreation | 2024 |
| Resolve Security GB Ltd | Administrative & support | 2022 |
| Resolve Tech Limited | Wholesale & retail | 2019 |
| Respect Homes Limited | Real estate | 2024 |
| Rest Easy Beds Limited | Manufacturing | 2011 |
| Restal Brown and Clannell Ltd | Construction | 2010 |
| Restal Brown and Clannell Manufacturing Ltd | Professional & scientific | 2010 |
| Restall Brown & Clanell Ltd | Wholesale & retail | 2010 |
| Restall Brown and Clanelle Manufacturing Ltd | Professional & scientific | 2010 |
| Revatravel Ltd | Administrative & support | 2026 |
| Revell Property Sussex Limited | Real estate | 2021 |
| Reverb Games Ltd | Information & communication | 2024 |
| Revival Clothing Ltd | Wholesale & retail | 2018 |
| Revival Renovations Ltd | Construction | 2021 |
| Revive by Emelda Limited | Other services | 2019 |
| Revive Hard Surface Repair Specialists Ltd | Construction | 2015 |
| Revive Sussex Services Ltd | Administrative & support | 2025 |
| Revolution Property Training Ltd | Education | 2019 |
| Reward Cloud Limited | Information & communication | 2016 |
| Rewind Coffee and Collectables Ltd | Hospitality | 2026 |
| Rewired.Earth CIC | Information & communication | 2021 |
| Rework Consulting Ltd | Information & communication | 2022 |
| Reynolds Carpentry & Construction Ltd | Construction | 2011 |
| Reza Balaghi Estates Ltd | Real estate | 2024 |
| RF Systems (H2O) Ltd | Professional & scientific | 2011 |
| RG Creative Communications Limited | Professional & scientific | 2017 |
| RGA Property Ltd | Real estate | 2018 |
| RH Connex Ltd | Administrative & support | 2025 |
| Rhino Boulder Ltd | Arts & recreation | 2020 |
| Rhythm Development Ltd | Education | 2022 |
| Ribg Limited | Professional & scientific | 2024 |
| Ribosome Scientific Ltd | Administrative & support | 2012 |
| Ribs & Co Restaurants Limited | Real estate | 2016 |
| Richard James Politz Ltd | Information & communication | 2019 |
| Richard Skudder Ltd | Health & social care | 2014 |
| Richard Wesencraft Consulting Limited | Financial services | 2014 |
| Richard's Cafe Limited | Hospitality | 2014 |
| Richards Robinson Enterprise Ltd | Information & communication | 2024 |
| Richborough Energy Park Limited | Construction | 2016 |
| Richer Image Limited | Information & communication | 2006 |
| Richmond Consultants Limited | Professional & scientific | 1976 |
| Richmond Trustees Limited | Real estate | 2011 |
| Richmont Hotels Limited | Hospitality | 2012 |
| Ridgeview Property Company Limited | Construction | 2015 |
| Ridgway Avenue Ltd | Construction | 2025 |
| Ridgway Property Limited | Real estate | 2024 |
| Rift Pixels Ltd | Information & communication | 2016 |
| RIG Enterprises Limited | Information & communication | 2018 |
| RIG Property Limited | Real estate | 2021 |
| Rigden Estates Sussex Ltd | Real estate | 2022 |
| Right Cars Vehicle Rental Limited | Administrative & support | 2020 |
| Right Light Films Limited | Information & communication | 2008 |
| Right Path 4 Ltd | Administrative & support | 2011 |
| Rightful Place Architectural Design Limited | Professional & scientific | 2020 |
| Rigid Kitchens Online Limited | Wholesale & retail | 2015 |
| RIH Consultancies Limited | Administrative & support | 2011 |
| Rikkies Ventures Limited | Manufacturing | 2026 |
| Ringarogy Media Limited | Information & communication | 2006 |
| Rioux Limited | Professional & scientific | 2009 |
| Riph Rock Music Ltd | Information & communication | 2022 |
| Ripley Chase RTM Company Limited | Households | 2011 |
| Ripley Trust Holdings Limited | Administrative & support | 2017 |
| Risen Energy Projects 1 Limited | Energy | 2011 |
| Riseview Properties Limited | Real estate | 1993 |
| Risktalk Ltd | Information & communication | 2016 |
| Ritchie Lambor Limited | Professional & scientific | 2008 |