| Reclear Residents Association Limited | Administrative & support | 1985 |
| Recliners Limited | Extraterritorial | 2006 |
| Recliners UK Limited | Manufacturing | 2003 |
| Rectagon Limited | Administrative & support | 2008 |
| Rectory Meadow Lane Limited | Households | 2024 |
| Recycling Plant and Machinery Ltd | Wholesale & retail | 2010 |
| Red Cotton Limited | Hospitality | 2023 |
| Red Dragon Hydroponics Limited | Wholesale & retail | 2018 |
| Red Dragon Project Controls Ltd | Professional & scientific | 2023 |
| Red Dragon Property Limited | Hospitality | 2015 |
| Red Dragon Removals and Storage Limited | Transport & logistics | 2021 |
| Red Dragon Repairs Limited | Construction | 2024 |
| Red Dragon RPL Limited | Wholesale & retail | 2025 |
| Red Dragon Sports Tipping Ltd | Arts & recreation | 2023 |
| Red Dragon Stores Limited | Wholesale & retail | 2026 |
| Red Jack Media Limited | Arts & recreation | 2004 |
| Red Lion Aldridge Limited | Hospitality | 2015 |
| Red Media Film & Photography Ltd | Information & communication | 2022 |
| Red Medtech Ltd | Professional & scientific | 2021 |
| Red Paving Ltd | Construction | 2019 |
| Red Security Multi Service Ltd | Wholesale & retail | 2019 |
| Red Snapper Developments Ltd | Construction | 2006 |
| Red Snapper Management Ltd | Professional & scientific | 2025 |
| Red Snapper Properties Ltd | Real estate | 2025 |
| Red Town Taverns Limited | Hospitality | 2017 |
| Red Zero Ltd | Professional & scientific | 2020 |
| RED3 Ltd | Professional & scientific | 2019 |
| Redefining Dining Co Ltd | Hospitality | 2023 |
| Redhawk Management Limited | Other services | 2014 |
| Redi 255 Limited | Extraterritorial | 2011 |
| Rediscover Media Limited | Information & communication | 2016 |
| Redmount Retail Group Ltd | Wholesale & retail | 2025 |
| Redsun 937 Limited | Hospitality | 2025 |
| Redwall Enterprises Limited | Financial services | 2025 |
| Redwood Care Solutions Limited | Administrative & support | 2023 |
| Redwood Joinery (Swansea) Limited | Manufacturing | 2011 |
| Redwood Wales Limited | Professional & scientific | 2004 |
| Reeds Property Rentals Limited | Real estate | 2021 |
| Reel-Fahst UK Services Limited | Transport & logistics | 2024 |
| Reemor Limited | Real estate | 2017 |
| Reeplay Sport Ltd | Wholesale & retail | 2023 |
| Rees & Wang Limited | Extraterritorial | 2013 |
| Rees Autos Ltd | Wholesale & retail | 2025 |
| Rees Bros (Damp Proofing) Swansea Limited | Construction | 1994 |
| Rees Bros Ltd | Extraterritorial | 2018 |
| Rees Brothers (Swansea) Limited | Construction | 1984 |
| Rees Building Solutions Limited | Construction | 2017 |
| Rees Element Limited | Administrative & support | 2014 |
| Rees Hiab and Haulage Ltd | Transport & logistics | 2020 |
| Rees Lewis Tinnitus Ltd | Wholesale & retail | 2013 |
| Rees Residential Properties Ltd | Real estate | 2021 |
| Rees Richards & Blyth Limited | Professional & scientific | 2026 |
| Rees-Jones Developments Limited | Construction | 2019 |
| Reescore Limited | Real estate | 2026 |
| Reeslectrics Limited | Real estate | 1959 |
| Reeves Investment Corporate Holdings Limited | Financial services | 2022 |
| Reeves Technical Services (Northants) Ltd | Construction | 2025 |
| Refined BIO Aesthetics Limited | Health & social care | 2021 |
| Refined Rose Ltd | Wholesale & retail | 2025 |
| Reflex Property Maintenance Limited | Construction | 2023 |
| Regal Swansea Ltd | Construction | 2023 |
| Regent's Luxury Lodges Limited | Construction | 2016 |
| Regimental Cleaning Services Ltd | Administrative & support | 2018 |
| Regimental Security Services Limited | Administrative & support | 2020 |
| Regis Solutions Ltd | Other services | 2025 |
| Rehan (Private) Limited | Wholesale & retail | 2019 |
| Reheat One Limited | Professional & scientific | 2024 |
| Rehitage Limited | Wholesale & retail | 2024 |
| Reign Salon Ltd | Other services | 2022 |
| Reimagined Materials Limited | Manufacturing | 2018 |
| Reina Beauty Ltd | Other services | 2024 |
| Rekab Property Management Limited | Real estate | 2022 |
| Relc Estates and Logistics Ltd | Transport & logistics | 2026 |
| Relc Holdings Ltd | Financial services | 2026 |
| Relc Property Limited | Real estate | 2026 |
| Relcom Solutions Limited | Other services | 2005 |
| REM Swansea Logistics Ltd | Transport & logistics | 2020 |
| Remarkably Creative Ltd | Wholesale & retail | 2023 |
| Remas Carpentry Contractors Limited | Manufacturing | 2019 |
| Remas Developments Limited | Real estate | 2023 |
| Remet Metal Limited | Wholesale & retail | 2023 |
| Remix Distribution Ltd | Administrative & support | 2013 |
| Renaissio Limited | Information & communication | 2021 |
| Renaspasa Ltd | Financial services | 2025 |
| Rend-Ability Limited | Construction | 2009 |
| Rendezvous Hair Design Limited | Other services | 2002 |
| Renesto & Co Limited | Professional & scientific | 2012 |
| Renew Mind Centre C.I.C. | Education | 2017 |
| Renew Smart Projects Ltd | Construction | 2025 |
| Renew Wellness Lounge Limited | Other services | 2025 |
| Renewable Home Energy Ltd | Construction | 2021 |
| Renewable Recruit Ltd | Administrative & support | 2025 |
| Renne Construction Ltd | Construction | 2022 |
| Rennwild Ltd | Manufacturing | 2024 |
| Reno Power Services Limited | Professional & scientific | 2017 |
| Renouf Financial Planning Ltd | Professional & scientific | 2025 |
| Renouf Wealth Management Ltd | Financial services | 2018 |
| Renovar Ltd | Real estate | 2024 |
| Rens Scaffolding Ltd | Construction | 2024 |
| Rent My Wardrobe Limited | Other services | 2022 |