| Swanbridge Farm Developments Ltd | Extraterritorial | 1995 |
| Swanbrink Limited | Real estate | 2001 |
| Swancast Limited | Real estate | 2001 |
| Swangyn Limited | Health & social care | 2025 |
| Swansbay Ltd | Construction | 2022 |
| Swansea & District Law Society | Professional & scientific | 1879 |
| Swansea & West Wales Limited | Hospitality | 2019 |
| Swansea 159 Ltd | Hospitality | 2019 |
| Swansea Accountancy Limited | Professional & scientific | 2013 |
| Swansea Accountancy Services (1996) Limited | Professional & scientific | 1996 |
| Swansea Accountants Ltd | Professional & scientific | 2021 |
| Swansea Acro and Dance Centre Ltd | Education | 2023 |
| Swansea Airport Limited | Transport & logistics | 2000 |
| Swansea Airport Stakeholders Alliance | Arts & recreation | 2021 |
| Swansea Allied Investments Ltd | Real estate | 2020 |
| Swansea Allied Medical Limited | Health & social care | 2013 |
| Swansea and Brecon Diocesan Board for Social Responsibility | Education | 2002 |
| Swansea Aquapark Ltd | Arts & recreation | 2024 |
| Swansea Autograss Club Limited | Arts & recreation | 1994 |
| Swansea Bathroom Solutions Ltd | Construction | 2020 |
| Swansea Bay Businesses | Other services | 2010 |
| Swansea Bay Cleaning Ltd | Administrative & support | 2025 |
| Swansea Bay Commercials Limited | Other services | 2004 |
| Swansea Bay Developments Limited | Real estate | 2016 |
| Swansea Bay Energy Partnership Limited | Professional & scientific | 2003 |
| Swansea Bay Home Care Services Limited | Health & social care | 2015 |
| Swansea Bay Homes Limited | Real estate | 2021 |
| Swansea Bay Human Resources Limited | Professional & scientific | 2020 |
| Swansea Bay Logistics Ltd | Transport & logistics | 2018 |
| Swansea Bay Physiotherapy Ltd | Health & social care | 2019 |
| Swansea Bay Property Ltd | Real estate | 2022 |
| Swansea Bay Property Management Limited | Real estate | 2016 |
| Swansea Bay Real Estate & Management Limited | Real estate | 2017 |
| Swansea Bay Street Markets Ltd | Wholesale & retail | 2013 |
| Swansea Bay Ventures Limited | Hospitality | 2016 |
| Swansea Bay Yarns Co Limited | Wholesale & retail | 2023 |
| Swansea Beach Plant Based Foods Ltd | Hospitality | 2022 |
| Swansea Bert MOT Limited | Wholesale & retail | 2023 |
| Swansea Bike Shop Limited | Wholesale & retail | 2010 |
| Swansea Boatyard Ltd | Manufacturing | 2025 |
| Swansea Breaks Ltd | Hospitality | 2025 |
| Swansea Brewing Company Limited | Manufacturing | 2022 |
| Swansea Burrows Railway Limited | Arts & recreation | 2016 |
| Swansea BUS Museum Ltd | Administrative & support | 2017 |
| Swansea Business Centre Limited | Extraterritorial | 2012 |
| Swansea Business Improvements Limited | Administrative & support | 2006 |
| Swansea Campuses UK Limited | Education | 2025 |
| Swansea Capital Finance Limited | Professional & scientific | 2025 |
| Swansea Carers' Centre | Health & social care | 2005 |
| Swansea Carpets Ltd | Wholesale & retail | 2025 |
| Swansea Cat Clinic Limited | Professional & scientific | 2022 |
| Swansea Celebrations Ltd | Administrative & support | 2025 |
| Swansea Chiropractic Clinic Limited | Health & social care | 2015 |
| Swansea City AFC Foundation | Education | 2008 |
| Swansea City Association Football Club Limited(The) | Arts & recreation | 1912 |
| Swansea City Football 2002 Limited | Arts & recreation | 2001 |
| Swansea City Football Club Limited | Arts & recreation | 2000 |
| Swansea City Vape Limited | Wholesale & retail | 2025 |
| Swansea College Tuition and Exam Centre Ltd | Education | 2024 |
| Swansea Commercial Body Builders Limited | Manufacturing | 1989 |
| Swansea Community Boat Trust | Transport & logistics | 2004 |
| Swansea Community Farm | Arts & recreation | 1999 |
| Swansea Decorating Services Limited | Construction | 2011 |
| Swansea Design & Build Construction Ltd | Construction | 2014 |
| Swansea Development SPV 1 Ltd | Construction | 2019 |
| Swansea Developments Limited | Construction | 2020 |
| Swansea Developments SPV 2 Ltd | Construction | 2020 |
| Swansea Discus Ltd | Wholesale & retail | 2024 |
| Swansea Drains Limited | Water & waste | 2011 |
| Swansea Driveways Ltd | Administrative & support | 2026 |
| Swansea DRY Cleaners Ltd | Other services | 2018 |
| Swansea Drydocks Limited | Transport & logistics | 2009 |
| Swansea Eats Limited | Wholesale & retail | 2021 |
| Swansea Education Group Ltd | Education | 2018 |
| Swansea Electrical Solutions Ltd | Construction | 2021 |
| Swansea Electronic Wholesale Limited | Wholesale & retail | 2019 |
| Swansea Employment Solutions Limited | Hospitality | 2026 |
| Swansea ENT Limited | Health & social care | 2012 |
| Swansea Facilities Management Company Limited | Arts & recreation | 2024 |
| Swansea Falcons CIC | Arts & recreation | 2022 |
| Swansea Fashion Week Ltd | Arts & recreation | 2026 |
| Swansea Fasteners & Engineering Supplies Limited | Wholesale & retail | 2006 |
| Swansea Festival of Music and the Arts | Arts & recreation | 1951 |
| Swansea Fireworks Ltd | Wholesale & retail | 2022 |
| Swansea Floatation & Wellness Centre Ltd | Other services | 2024 |
| Swansea Forge Limited | Manufacturing | 2011 |
| Swansea Freehold Limited | Other services | 2009 |
| Swansea GAS and OIL Limited | Construction | 2025 |
| Swansea GAS Services Ltd | Construction | 2023 |
| Swansea Golf Lessons Ltd | Education | 2015 |
| Swansea Guitar Studios Limited | Education | 1996 |
| Swansea Gymnastics Centre | Arts & recreation | 2014 |
| Swansea Hackspace | Other services | 2013 |
| Swansea Hairstyle Ltd | Other services | 2019 |
| Swansea Hand Surgery CYF | Health & social care | 2023 |
| Swansea HD Brickwork Ltd | Construction | 2018 |
| Swansea Health Solutions Ltd | Health & social care | 2011 |
| Swansea Heating & Lighting Co. Limited | Real estate | 1976 |
| Swansea Historic Vehicle Register Limited | Administrative & support | 2001 |
| Swansea Home Improvements Limited | Administrative & support | 2006 |