| Riverside Vets Limited | Professional & scientific | 2010 |
| RJ Estimating Ltd | Professional & scientific | 2023 |
| RJ Plastering Ltd | Construction | 2025 |
| RJG Accountants AKH Limited | Professional & scientific | 2018 |
| RJG Specialist Installations Ltd | Construction | 2023 |
| RJM Software Limited | Information & communication | 2025 |
| RJS Convenience Store Limited | Wholesale & retail | 2024 |
| RJS Property Maintenance Ltd | Construction | 2022 |
| RK (Eastleigh) Properties Ltd | Real estate | 2019 |
| RKJ Ltd | Real estate | 2026 |
| RLA Consulting Limited | Administrative & support | 2026 |
| RLJ Holdings Ltd | Financial services | 2023 |
| RMD Carpentry Services Ltd | Manufacturing | 2023 |
| Rmet Investments Limited | Real estate | 2021 |
| RMG Enterprises Ltd | Professional & scientific | 2024 |
| RMJ Dental Laboratories Ltd | Health & social care | 2003 |
| RMR Plastering Ltd | Construction | 2024 |
| RMV Limited | Real estate | 2018 |
| RMV Trading Ltd | Wholesale & retail | 2021 |
| ROB COE Limited | Information & communication | 2014 |
| ROB Hales Design Limited | Professional & scientific | 2015 |
| ROB Mott Holdings Limited | Financial services | 2026 |
| Robert Rose Carpentry Limited | Manufacturing | 2019 |
| Robert Rose Investments Limited | Real estate | 2021 |
| Robert Santa Limited | Hospitality | 2011 |
| Robert Shipp and Daughter Limited | Other services | 2011 |
| Roberts Holdings (Southampton) Limited | Financial services | 2018 |
| Robigus Limited | Financial services | 2019 |
| Robins Nest Emporium Fareham Ltd | Wholesale & retail | 2018 |
| Robinson Road (Hampshire) Limited | Professional & scientific | 2023 |
| Roboarm Limited | Information & communication | 2025 |
| ROC Marine Solutions Limited | Manufacturing | 2018 |
| Rock and Stone Consulting Ltd | Administrative & support | 2010 |
| Rock Towers Property Investment Limited | Real estate | 2021 |
| Rocker (London) Ltd | Arts & recreation | 2019 |
| Rocket HOLDING5 Limited | Real estate | 2025 |
| Rocketship Studio Limited | Information & communication | 2012 |
| Rockstable Ltd | Real estate | 2023 |
| Rocktide Ltd | Professional & scientific | 2026 |
| Rodd & Gunn UK Limited | Wholesale & retail | 2019 |
| ROE Green Management Company Limited | Households | 2000 |
| Roebuck Close (Eastleigh) Management Limited | Households | 2022 |
| Roger's Homes and Developments Ltd | Construction | 2020 |
| Rohsun Ltd | Health & social care | 2013 |
| Rokshore Commercial Ltd | Construction | 2023 |
| Rollerb Limited | Extraterritorial | 2024 |
| Rolling Stock Technical Services Limited | Manufacturing | 2014 |
| Romsey Heritage Services Limited | Construction | 2025 |
| Romsey Reclamation Limited | Wholesale & retail | 1998 |
| Romsey Retail Limited | Wholesale & retail | 2026 |
| Ronald Brenton Limited | Construction | 2025 |
| Ronexis Limited | Wholesale & retail | 2004 |
| Roni Phillips Landscapes Limited | Administrative & support | 2002 |
| Roof Guard South Ltd | Construction | 2023 |
| Roofsol Limited | Energy | 2023 |
| Rookesbury Estates Limited | Real estate | 1970 |
| Rookesbury Events Limited | Arts & recreation | 2012 |
| Rooted & Regulated Ltd | Education | 2026 |
| Rosa-Luxemburg-Stiftung Great Britain Limited | Other services | 2019 |
| Rosbm Limited | Real estate | 2024 |
| Roscoe & James Renovations Limited | Construction | 2022 |
| Rose Property Holdings Limited | Real estate | 2020 |
| Rosemary Court Residents Association (Bitterne) Limited | Real estate | 2002 |
| Rother Properties Limited | Real estate | 1987 |
| Rothmans CF Limited | Professional & scientific | 2022 |
| Rotortech Limited | Manufacturing | 2014 |
| Roughton & Partners Limited | Professional & scientific | 1985 |
| Roughton Group Limited | Professional & scientific | 2013 |
| Roughton International Limited | Professional & scientific | 1987 |
| Roughton Limited | Professional & scientific | 2024 |
| Roughton South Ltd | Professional & scientific | 1995 |
| Roundlight Limited | Professional & scientific | 2012 |
| Route 23 Recruitment Ltd | Administrative & support | 2022 |
| Route Geographic Consultants Limited | Professional & scientific | 2015 |
| Rowden's Tree Consultancy and Training Ltd | Agriculture & fishing | 2023 |
| Rowe & Co Homes Group Limited | Real estate | 2023 |
| Rowe and Co Homes (Chandlers Ford) Limited | Real estate | 2023 |
| Rowe Property Management Services Ltd | Real estate | 2007 |
| Rowelectric Ltd | Manufacturing | 2022 |
| Rowena Bookkeeping & Accounting Limited | Professional & scientific | 2022 |
| Rowker (Hampshire) Limited | Hospitality | 2020 |
| Roxeth Energy Consulting Limited | Professional & scientific | 2024 |
| Roxeve Pharmaceuticals Ltd | Wholesale & retail | 2014 |
| Royale Roofing Ltd | Construction | 2024 |
| Roycian (Nominee) Limited | Financial services | 2023 |
| Roycian Ltd | Financial services | 2014 |
| RPC Software Engineering Limited | Information & communication | 1994 |
| RS & RS Transport Ltd | Transport & logistics | 2022 |
| RS Building and Joinery Ltd | Construction | 2024 |
| RS Computer Solutions Ltd. | Information & communication | 1997 |
| RS International Spill Solutions Limited | Professional & scientific | 2022 |
| RSS Autos Limited | Wholesale & retail | 2015 |
| Rsvs Holdings Limited | Professional & scientific | 2024 |
| Rswsound Ltd | Construction | 2022 |
| Ruasha Productions Ltd | Information & communication | 2026 |
| Ruby Alice Limited | Administrative & support | 2013 |
| Rudol Ltd | Financial services | 2014 |
| Rufus Consulting Ltd | Professional & scientific | 2014 |
| RUM Entertainment Limited | Arts & recreation | 2026 |
| RUM Events Limited | Hospitality | 2025 |