| Radio Slawian Ltd | Manufacturing | 2022 |
| Radio Victory Ltd | Information & communication | 2020 |
| Radley Trading Limited | Information & communication | 2017 |
| Radweb Ltd | Information & communication | 2007 |
| Radweb Ventures Limited | Information & communication | 2021 |
| Rafbar Plumbing & Heating Limited | Construction | 2017 |
| Rahman Import Export Ltd | Wholesale & retail | 2023 |
| Rail Safety APD Ltd | Transport & logistics | 2014 |
| Railway Property Developments Limited | Construction | 2024 |
| Rainbow ARK Productions Ltd | Information & communication | 2025 |
| Rainesway Construction Limited | Construction | 2014 |
| Rainguard Roofing Solutions Ltd | Construction | 2026 |
| Rainmaker Irrigation Company Limited | Administrative & support | 1995 |
| Raising Partners Limited | Professional & scientific | 2017 |
| Raja and Sons Property Ltd | Real estate | 2018 |
| Ralf Housing Ltd | Real estate | 2025 |
| Ralston Consultancy Ltd | Information & communication | 2018 |
| RAM Interiors Ltd | Construction | 2022 |
| RAM2 Ltd | Financial services | 2025 |
| Ramkor Limited | Professional & scientific | 2016 |
| Rampage Promotions Ltd | Administrative & support | 2026 |
| Rana Nabeel Limited | Wholesale & retail | 2025 |
| Rancho Express Portsmouth Ltd | Hospitality | 2021 |
| Rancho Steak House Limited | Hospitality | 2007 |
| RAP IT Ltd | Wholesale & retail | 2018 |
| Rapid Build & Secure Ltd | Construction | 2025 |
| Rapid Computer Solutions Limited | Information & communication | 2026 |
| Rapid Flush Limited | Construction | 2026 |
| Rapid Response Solutions Holdings Limited | Real estate | 2005 |
| Rapid Response Solutions Limited | Transport & logistics | 2000 |
| Rapid Roofing & Building Maintenance Ltd | Construction | 2023 |
| Rapid Vehicles (Hampshire) Ltd | Wholesale & retail | 2025 |
| Rask Group Ltd | Financial services | 2024 |
| Raspberry Bush Developments Limited | Construction | 2017 |
| Rattly and RAW Limited | Arts & recreation | 2014 |
| Ravelin Group Limited | Administrative & support | 2017 |
| Ravelin Housing Limited | Construction | 2020 |
| Ravelin Property Limited | Administrative & support | 2017 |
| RAW Garage Ltd | Wholesale & retail | 2012 |
| RAW Reporting Ltd | Health & social care | 2025 |
| Rawa Kebab Ltd | Hospitality | 2025 |
| Rawaz Hand Car Wash Ltd | Administrative & support | 2025 |
| Rawmans Ltd | Wholesale & retail | 2017 |
| Razors Barber Ltd | Other services | 2022 |
| Razzamatazz Limited | Professional & scientific | 1992 |
| RB Decorators Ltd | Construction | 2026 |
| RB GAS and Heating Services Ltd | Construction | 2021 |
| RB Rubber Solutions Ltd | Manufacturing | 2024 |
| Rbaxter@Letsgouk Ltd | Education | 2014 |
| RBCM2 Limited | Arts & recreation | 2016 |
| RBS Automotive Group Management Ltd | Professional & scientific | 2020 |
| RC Property Southern Ltd | Professional & scientific | 2022 |
| RCA Auto Limited | Transport & logistics | 2026 |
| RCG Elgin Ltd | Real estate | 2019 |
| RCN Local Services Limited | Administrative & support | 2006 |
| RCR Property Maintenance Ltd | Construction | 2023 |
| RD Medical Aesthetics Ltd | Health & social care | 2024 |
| RDA Clinical and Care Services Ltd | Health & social care | 2026 |
| RDL Commercial Limited | Construction | 2015 |
| RDL Fire Protection Limited | Other services | 2024 |
| RDL Group (South) Limited | Financial services | 2023 |
| RDL Residential Limited | Real estate | 2023 |
| RDS Project Management Limited | Professional & scientific | 2024 |
| RDS Projects Group Limited | Professional & scientific | 2024 |
| Re:Worx Limited | Wholesale & retail | 2003 |
| Reactive Contractors Limited | Administrative & support | 2022 |
| Reading Gynaecology Ltd | Health & social care | 2023 |
| Reading SA Ltd | Hospitality | 2019 |
| Real Blends Ltd | Manufacturing | 2025 |
| Real Care Professionals Limited | Administrative & support | 2017 |
| Real GEM Properties Ltd | Real estate | 2021 |
| Reap Property LLP | | 2017 |
| Rebeccaflcoaching Ltd | Health & social care | 2022 |
| Rebel O'Brien Ltd | Professional & scientific | 2019 |
| Rebellious Business Ltd | Professional & scientific | 2017 |
| Recombix Ltd | Information & communication | 2015 |
| Recovery Space Genies Ltd | Wholesale & retail | 2026 |
| Recruit 4CARE Ltd | Administrative & support | 2016 |
| Recruit-Ai Information Orchestrators Ltd. | Administrative & support | 2017 |
| Recycle Southern Aggregates Ltd | Water & waste | 2021 |
| Recycle Southern Limited | Water & waste | 2013 |
| Recycled Office Solutions Limited | Wholesale & retail | 2019 |
| Red Balloon Cafe Limited | Hospitality | 2022 |
| Red Dragon Corporation Ltd | Professional & scientific | 2025 |
| Red Hot International Ltd | Wholesale & retail | 2023 |
| Red Penguin Associates Ltd | Professional & scientific | 2007 |
| Red Penguin Business Ltd | Financial services | 2019 |
| Red Penguin Holdings Ltd | Financial services | 2019 |
| Red Penguin International Ltd | Financial services | 2019 |
| Red Penguin Marine Ltd | Financial services | 2019 |
| Red Restaurants Southern Limited | Hospitality | 2013 |
| Red Ridge Properties Limited | Real estate | 2014 |
| Red Squirrel OT CIC | Health & social care | 2023 |
| Red Star Accountancy Ltd | Professional & scientific | 2016 |
| Redbay Ltd | Professional & scientific | 2022 |
| Redbridge Care Ltd | Other services | 2017 |
| Redcliffe Gardens RTM Company Limited | Professional & scientific | 2005 |
| Redcliffe Gardens Tennants Association Limited | Households | 1993 |
| Redeemed Christian Church of GOD Discipleship Centre Portsmouth | Other services | 2018 |
| Redfern Engineering Company LLP | | 2015 |