| Sweet Candy Corner Ltd | Arts & recreation | 2011 |
| Sweet P Beauty Salon Limited | Other services | 2019 |
| Sweet Peach Hospitality Services Ltd | Hospitality | 2022 |
| Sweetkare Ltd | Health & social care | 2020 |
| Sweetness Providers Limited | Health & social care | 2022 |
| Swenlink Ltd | Professional & scientific | 2025 |
| SWG Plant Hire Ltd | Administrative & support | 2026 |
| Swgrabhire Ltd | Water & waste | 2023 |
| Swift Business Contractors Ltd | Professional & scientific | 2018 |
| Swift Fill Ltd | Wholesale & retail | 2024 |
| Swift Garage Ltd | Other services | 2019 |
| Swift Tyres Swindon Ltd | Manufacturing | 2024 |
| Swift Van Hub Ltd | Professional & scientific | 2025 |
| Swift-Services Limited | Administrative & support | 2018 |
| Swiftaccess Limited | Information & communication | 2022 |
| Swiftautos Care Limited | Wholesale & retail | 2025 |
| Swiftbrick Limited | Construction | 2019 |
| Swiftchain Ltd | Wholesale & retail | 2023 |
| Swillbrook Services Limited | Professional & scientific | 2018 |
| Swim Buddies LLP | | 2018 |
| Swim East LLP | | 2024 |
| Swim School of Abingdon Limited | Education | 2019 |
| Swim West LLP | | 2011 |
| SWIM4FUN Limited | Arts & recreation | 2010 |
| Swimming in Swindon Ltd | Education | 2024 |
| Swindon & Cricklade Railway | Transport & logistics | 1997 |
| Swindon & District Citizens Advice Bureau | Information & communication | 2001 |
| Swindon & Gloucestershire Mind Ltd | Health & social care | 2017 |
| Swindon 114 Limited | Manufacturing | 2012 |
| Swindon Advocacy Movement | Other services | 1997 |
| Swindon Air Conditioning Ltd | Energy | 2025 |
| Swindon Airport Cars Limited | Transport & logistics | 2020 |
| Swindon Airport Service Limited | Transport & logistics | 2006 |
| Swindon Airport Taxi Ltd | Transport & logistics | 2024 |
| Swindon Airsoft Supplies Ltd | Other services | 2009 |
| Swindon Allstars Limited | Arts & recreation | 2011 |
| Swindon Analysis Solutions Limited | Professional & scientific | 2017 |
| Swindon and Wiltshire Skip Hire Ltd | Extraterritorial | 2022 |
| Swindon Artists Forum CIC | Arts & recreation | 2024 |
| Swindon Asbestos Removals Ltd | Construction | 2016 |
| Swindon Asbestos Services Ltd | Construction | 2016 |
| Swindon Asbestos Solutions Ltd | Construction | 2016 |
| Swindon Automotive Repair Ltd | Wholesale & retail | 2024 |
| Swindon Autos Ltd | Wholesale & retail | 2024 |
| Swindon Baileys Corner Ltd | Wholesale & retail | 2019 |
| Swindon Bearings Limited | Wholesale & retail | 2012 |
| Swindon BED Centre Limited | Wholesale & retail | 2003 |
| Swindon Bengali Cultural Society | Health & social care | 2025 |
| Swindon BID Ltd | Other services | 2026 |
| Swindon Birth School Ltd | Education | 2025 |
| Swindon Bookbinders Ltd | Manufacturing | 2013 |
| Swindon BR Ltd | Real estate | 2023 |
| Swindon Bridge Street Ltd | Hospitality | 2025 |
| Swindon Brunel ABC CIC | Education | 2021 |
| Swindon Building Projects Ltd | Construction | 2025 |
| Swindon CAB & Car Rental Ltd | Transport & logistics | 2023 |
| Swindon Cambelt Centre Limited | Wholesale & retail | 2010 |
| Swindon Car & Van Limited | Administrative & support | 2013 |
| Swindon Car Body Repair Limited | Wholesale & retail | 2012 |
| Swindon Car Sales - SCS Ltd | Wholesale & retail | 2018 |
| Swindon Caravan Centre Limited | Wholesale & retail | 2003 |
| Swindon Care Services Ltd | Health & social care | 2023 |
| Swindon Carers Centre | Health & social care | 1997 |
| Swindon Cars Limited | Wholesale & retail | 2006 |
| Swindon Ccrc Trust | Other services | 2018 |
| Swindon Cervejaria Limited | Manufacturing | 2026 |
| Swindon Chapel Farm Solar PLC | Energy | 2015 |
| Swindon Childcarers Ltd. | Health & social care | 1989 |
| Swindon Childrens Bike Coaching Limited | Education | 2023 |
| Swindon Commercials Ltd | Wholesale & retail | 2026 |
| Swindon Common Farm Solar Community Interest PLC | Energy | 2015 |
| Swindon Community Action Limited | Transport & logistics | 2019 |
| Swindon Community Church | Other services | 2010 |
| Swindon Concrete Limited | Construction | 2022 |
| Swindon Consultant Anaesthetists Limited | Health & social care | 2003 |
| Swindon Culture Collective CIC | Arts & recreation | 2025 |
| Swindon Dance | Arts & recreation | 2005 |
| Swindon Darts and Print Hub Limited | Manufacturing | 2024 |
| Swindon Delight Kebabs Ltd | Hospitality | 2026 |
| Swindon Delight Limited | Hospitality | 2025 |
| Swindon Demolition Limited | Construction | 2011 |
| Swindon Dental Laboratory Limited | Health & social care | 2005 |
| Swindon Design and Development Limited | Information & communication | 2012 |
| Swindon Drywall Ltd | Construction | 2015 |
| Swindon EAR Clinic Limited | Health & social care | 2026 |
| Swindon Education Group Ltd | Education | 2024 |
| Swindon Electricians Ltd | Administrative & support | 2016 |
| Swindon Electronic Services Limited | Information & communication | 1985 |
| Swindon Engineering Metalworkers Limited | Manufacturing | 1989 |
| Swindon Epcs Ltd | Real estate | 2022 |
| Swindon Event Services Ltd | Administrative & support | 2023 |
| Swindon Executive Cars Ltd | Transport & logistics | 2019 |
| Swindon Executive Holiday Cars Ltd | Transport & logistics | 2023 |
| Swindon Export Direct Limited | Other services | 2020 |
| Swindon Express Chauffeur Ltd | Transport & logistics | 2019 |
| Swindon Film Festival CIC | Arts & recreation | 2023 |
| Swindon Financial Planning Limited | Financial services | 2013 |
| Swindon Flooring Company Limited | Construction | 1987 |
| Swindon Foster Carers Association Community Interest Company | Health & social care | 2026 |
| Swindon Gardening Services Ltd | Arts & recreation | 2025 |