| Rowes Homes Ltd | Real estate | 2022 |
| Rowland Jones Consulting Limited | Professional & scientific | 2025 |
| Rowlands Foodlogix Ltd | Hospitality | 2024 |
| Rowlands Rentals Limited | Real estate | 2020 |
| Roxan Animal Ltd | Wholesale & retail | 2019 |
| ROY Hopkins (Engineers) Limited | Administrative & support | 1995 |
| Royal Institution of South Wales | Arts & recreation | 1883 |
| Royal Roofing Swansea Limited | Construction | 2023 |
| ROZ & Kirsty Photography Limited | Professional & scientific | 2018 |
| RP Catering Services Ltd | Hospitality | 2021 |
| RPA Swansea Ltd | Wholesale & retail | 2015 |
| RPAR10 Ltd | Real estate | 2022 |
| RPAR11 Limited | Wholesale & retail | 2025 |
| Rpda Aviation Ltd | Wholesale & retail | 2023 |
| RPL Swansea Ltd | Wholesale & retail | 2023 |
| RPM Company Secretary Limited | Administrative & support | 2023 |
| RPM Metals and Energy Limited | Professional & scientific | 2011 |
| RR Food & Wine Limited | Wholesale & retail | 2022 |
| RR Logistics & Plants Ltd | Transport & logistics | 2025 |
| RRJ Consulting Ltd | Wholesale & retail | 2019 |
| RS Lion Limited | Transport & logistics | 2017 |
| RSM Cars Limited | Wholesale & retail | 2026 |
| RSM Foods Limited | Wholesale & retail | 2025 |
| RSM Stores UK Limited | Wholesale & retail | 2025 |
| Rsps Holdings Limited | Real estate | 2023 |
| Rsps Properties Limited | Real estate | 2024 |
| RSS Engineering Group UK Ltd | Manufacturing | 2006 |
| RSS Fitting (South Wales) Limited | Other services | 2017 |
| RT Training and Skills Ltd | Education | 2021 |
| RTB Electrical Services Limited | Construction | 2017 |
| Rtec Garage Ltd | Wholesale & retail | 2016 |
| RTS89 Limited | Health & social care | 2023 |
| Ruach Capital Ltd | Information & communication | 2022 |
| Rualgo Ltd | Real estate | 2020 |
| Rubber Duck Consulting Ltd | Information & communication | 2018 |
| Rubicon Play Limited | Manufacturing | 2006 |
| Ruckas Limited | Professional & scientific | 2004 |
| Rufus Lewis Management Company Limited | Households | 2021 |
| Rugby MAD Limited | Professional & scientific | 2014 |
| Rugby MAD Real Estate Limited | Real estate | 2017 |
| Rugged Rock Ltd | Education | 2021 |
| Rumpole Limited | Wholesale & retail | 2003 |
| Run Afan Forest Ltd | Arts & recreation | 2020 |
| Runtech (North) Limited | Administrative & support | 2010 |
| Runtech European Group Ltd | Financial services | 2021 |
| Runtech Holdings Ltd | Financial services | 2017 |
| Runtech Limited | Wholesale & retail | 1996 |
| Ruscor Designs Limited | Administrative & support | 2016 |
| Russell Waters & Co. Ltd | Construction | 2020 |
| Ruta Cafe Ltd | Hospitality | 2024 |
| Ruta Swansea Ltd | Hospitality | 2025 |
| Ruth Miltonjones Events Limited | Wholesale & retail | 2023 |
| Ruva Rentals Limited | Real estate | 2025 |
| RV Manufacturing Ltd | Manufacturing | 2013 |
| RVA Holding Limited | Manufacturing | 2019 |
| RVS Griffiths & SON Ltd | Professional & scientific | 2016 |
| RWD Property Ltd | Real estate | 2026 |
| Rwdev Ltd | Information & communication | 2025 |
| RX Partners (Holdings) Ltd | Wholesale & retail | 2026 |
| Ryan Hubbard Haulage Ltd | Transport & logistics | 2015 |
| Rybond Couriers Ltd | Transport & logistics | 2019 |
| Rycon Developments Limited | Real estate | 1961 |
| Ryehill Properties Limited | Professional & scientific | 1991 |
| Ryeland Flock Book Society Limited | Agriculture & fishing | 1905 |
| Ryjo Construction Ltd | Construction | 2019 |
| Rylo Limited | Financial services | 2011 |
| Ryugin Limited | Hospitality | 2022 |
| S & a Scrap Metal Limited | Water & waste | 2018 |
| S & B Solutions Limited | Information & communication | 2011 |
| S & G Soils Limited | Transport & logistics | 2009 |
| S & H Coughlan Construction & Sons Ltd | Construction | 2019 |
| S & J Bratton Developments Ltd | Construction | 2015 |
| S & L Accountancy Services Ltd | Professional & scientific | 2017 |
| S & M Industrial Services Limited | Administrative & support | 2006 |
| S & R Transport Services Limited | Transport & logistics | 2006 |
| S & TW Properties Ltd | Real estate | 2026 |
| S a and SON Swansea Transport Ltd | Transport & logistics | 2024 |
| S a Building Maintenance Ltd | Construction | 2023 |
| S a Laser Clinic Ltd | Other services | 2008 |
| S a Morgan AI Feibion CYF | Transport & logistics | 2022 |
| S and S Motors(Uk) Ltd | Wholesale & retail | 2018 |
| S B Commercials Ltd | Other services | 2015 |
| S B Hotel Ltd | Hospitality | 2020 |
| S C P Construction Cost Consultants Limited | Professional & scientific | 2006 |
| S Charles Estates Ltd | Construction | 2021 |
| S D Harris Car Sales Ltd | Wholesale & retail | 2004 |
| S D W Plumbing & Heating South Wales Ltd | Construction | 2024 |
| S G Plant Wales Limited | Transport & logistics | 2014 |
| S I Stats Ltd | Extraterritorial | 2017 |
| S I Surveys Limited | Professional & scientific | 2021 |
| S J Bessent Construction Services Limited | Construction | 2003 |
| S J Bevan Carpentry & Joinery Ltd | Construction | 2003 |
| S J Fishing Limited | Agriculture & fishing | 2025 |
| S L J Limited | Construction | 2005 |
| S M Enterprise(Wales) Ltd | Wholesale & retail | 2016 |
| S M Pearson Ltd | Wholesale & retail | 2014 |
| S M Richmond Ltd | Construction | 2022 |
| S Manners Investment Ltd | Financial services | 2019 |
| S Manners Ltd | Financial services | 2018 |
| S Mansell Properties Ltd | Real estate | 2022 |