| Swansea Homes & Gardens Ltd | Construction | 2017 |
| Swansea Hospitality Solutions Limited | Hospitality | 2020 |
| Swansea Indoor Bowls Ltd | Arts & recreation | 2014 |
| Swansea Industrial Components Limited | Manufacturing | 1992 |
| Swansea Innovations Limited | Professional & scientific | 1998 |
| Swansea Jewellery Repairs Limited | Other services | 2023 |
| Swansea Kebab Ltd | Hospitality | 2023 |
| Swansea Laptops SW Limited | Other services | 2018 |
| Swansea Laserzone Limited | Arts & recreation | 2021 |
| Swansea Legal Solutions Ltd | Professional & scientific | 2018 |
| Swansea Living Solutions Limited | Health & social care | 2017 |
| Swansea Logs Ltd | Other services | 2024 |
| Swansea Maritime Quarter Freehold Limited | Other services | 2016 |
| Swansea Materials Research & Testing Ltd | Professional & scientific | 2009 |
| Swansea Medical Imaging Limited | Health & social care | 2017 |
| Swansea Mencap Society | Health & social care | 2020 |
| Swansea Minibus Hire Ltd | Transport & logistics | 2016 |
| Swansea Minimarket Ltd | Wholesale & retail | 2023 |
| Swansea Motor Vehicle Contracts Limited | Transport & logistics | 2008 |
| Swansea Multicultural Women's Resource and Training Centre Limited | Education | 1991 |
| Swansea Music Hub CIC | Arts & recreation | 2024 |
| Swansea Muslim Funeral Services Ltd | Other services | 2025 |
| Swansea Observatory Limited | Hospitality | 2013 |
| Swansea Offset Supplies Limited | Hospitality | 1987 |
| Swansea Orthopaedics Limited | Health & social care | 2008 |
| Swansea Orthopaedics Property Ltd | Real estate | 2025 |
| Swansea Pain Clinic Limited | Health & social care | 2017 |
| Swansea Pain Relief Ltd | Health & social care | 2023 |
| Swansea Phone Tech Ltd | Wholesale & retail | 2019 |
| Swansea Physiotherapy Ltd | Health & social care | 2012 |
| Swansea Pilates Ltd | Health & social care | 2018 |
| Swansea Pizza & Kebab House Limited | Hospitality | 2022 |
| Swansea Plumb Point Holdings Limited | Financial services | 2023 |
| Swansea Plumb Point Ltd | Wholesale & retail | 1996 |
| Swansea Plumbers & Boilers Ltd | Construction | 2025 |
| Swansea Pole & Aerial Academy Ltd | Arts & recreation | 2019 |
| Swansea Print Workshop | Arts & recreation | 2000 |
| Swansea Printing Co Ltd | Manufacturing | 2023 |
| Swansea Pro Build Ltd | Construction | 2025 |
| Swansea Professional Painters Ltd | Construction | 2022 |
| Swansea Properties Ltd | Real estate | 2010 |
| Swansea Property Agents Limited | Real estate | 2010 |
| Swansea Property Group Ltd | Real estate | 2024 |
| Swansea Radiators and Autoparts Limited | Wholesale & retail | 2003 |
| Swansea Readymix Concrete Ltd | Manufacturing | 2023 |
| Swansea Real Estate Ltd | Real estate | 2023 |
| Swansea Recycling (Furniture) Ltd | Water & waste | 2020 |
| Swansea Refrigeration Ltd | Manufacturing | 2016 |
| Swansea Removals Limited | Transport & logistics | 2022 |
| Swansea RFC Memorabilia Community Interest Company | Arts & recreation | 2013 |
| Swansea Safety Limited | Professional & scientific | 2023 |
| Swansea Safety Solutions Ltd | Real estate | 2025 |
| Swansea Sales UK Limited | Wholesale & retail | 2019 |
| Swansea Sand & Gravel Ltd | Transport & logistics | 2018 |
| Swansea Sand and Stone Limited | Transport & logistics | 2014 |
| Swansea Sausage Company Ltd | Extraterritorial | 2011 |
| Swansea Screed and Concrete Limited | Manufacturing | 2012 |
| Swansea Self Storage Limited | Transport & logistics | 1996 |
| Swansea Sharks Swim School Ltd | Arts & recreation | 2010 |
| Swansea Shawarma Ltd | Hospitality | 2026 |
| Swansea Shine Carwash Ltd | Administrative & support | 2025 |
| Swansea Showers & Bathrooms Limited | Wholesale & retail | 1989 |
| Swansea Sixth-Form College Wales Ltd | Education | 2013 |
| Swansea Skiphire Ltd. | Water & waste | 2025 |
| Swansea Skips Ltd | Water & waste | 2008 |
| Swansea Softwash & Pressure Washing Ltd | Water & waste | 2025 |
| Swansea Spaces Limited | Real estate | 2008 |
| Swansea Sports Medicine Ltd | Health & social care | 2018 |
| Swansea Spotlight Ltd | Professional & scientific | 2024 |
| Swansea Stadium Management Company Limited | Arts & recreation | 2004 |
| Swansea Stadium Premier Club Limited | Other services | 2004 |
| Swansea Steel Products Limited | Professional & scientific | 1933 |
| Swansea Strength & Conditioning Ltd | Other services | 2017 |
| Swansea Student Homes Ltd | Real estate | 2014 |
| Swansea Student Houses Limited | Construction | 2016 |
| Swansea Surveys Construction Ltd | Construction | 2018 |
| Swansea Surveys Holdings Ltd | Real estate | 2018 |
| Swansea Surveys Holdings Manchester Ltd | Real estate | 2024 |
| Swansea Surveys Ltd | Construction | 2011 |
| Swansea Surveys RL Ltd | Construction | 2017 |
| Swansea Sweetie JAR Limited | Wholesale & retail | 2016 |
| Swansea Tennis and Squash Club Limited | Arts & recreation | 2015 |
| Swansea Trade Sales Limited | Wholesale & retail | 2016 |
| Swansea Trade Windows Ltd | Manufacturing | 2011 |
| Swansea Trading Services Ltd | Hospitality | 2026 |
| Swansea Training Limited | Education | 2018 |
| Swansea Travel Limited | Transport & logistics | 2022 |
| Swansea Tribology Services Limited | Professional & scientific | 1994 |
| Swansea Turbine Services Limited | Manufacturing | 2025 |
| Swansea Tyre Centre Ltd | Wholesale & retail | 2024 |
| Swansea Tyre Place Limited | Wholesale & retail | 2017 |
| Swansea University Students’ Union | Other services | 2023 |
| Swansea Uplands RFC Limited | Arts & recreation | 2013 |
| Swansea Vale 4 X 4 Limited | Wholesale & retail | 2020 |
| Swansea Valley Accountancy Ltd | Professional & scientific | 2025 |
| Swansea Valley Exhaust and Tyre Centre Limited | Wholesale & retail | 2014 |
| Swansea Valley Forge Ltd | Manufacturing | 2018 |
| Swansea Valley Properties Limited | Other services | 2004 |
| Swansea Valley Publishing Ltd | Information & communication | 2026 |
| Swansea Vape Shop Limited | Wholesale & retail | 2025 |