| Sheridan PP Ltd | Real estate | 2020 |
| Sheridan Property Portfolio Ltd | Real estate | 2016 |
| Sherwell Court Uphill Management Limited | Households | 2023 |
| Sherwood Lodge WSM Management Ltd | Households | 2024 |
| Shev Limited | Administrative & support | 2017 |
| Shevron Limited | Wholesale & retail | 1990 |
| Shield Fabrications Limited | Manufacturing | 2025 |
| Ship House Limited | Households | 2018 |
| Shiraz Food Southwest Ltd | Hospitality | 2024 |
| Shorelines (Portishead) Management Company Limited | Households | 2011 |
| Showtechs Promotions Ltd | Administrative & support | 2018 |
| Shrubbery Avenue Management Company Limited | Households | 2008 |
| Shuanxi Chinese Takeaway Ltd | Hospitality | 2025 |
| Shukria Weston Ltd | Hospitality | 2019 |
| Shuny's Farm & Livery Ltd | Agriculture & fishing | 2021 |
| Shuraroha Ltd | Arts & recreation | 2015 |
| Shurley's Store Limited | Wholesale & retail | 2026 |
| Shut UP and Fish Limited | Other services | 2014 |
| Shutter Bliss Photography LLP | | 2017 |
| Sian Parry Jones Ltd | Professional & scientific | 2011 |
| Sibley Enterprises Limited | Administrative & support | 2006 |
| Sidney & Eden Portishead Ltd | Hospitality | 2024 |
| Sidney and Eden Ltd | Hospitality | 2020 |
| Sienna Healthcare Limited | Health & social care | 2015 |
| Sign & Print Factor Ltd | Professional & scientific | 2019 |
| Signature Stainless Limited | Wholesale & retail | 2012 |
| Silver Street Nailsea (Management Company) Limited | Real estate | 1983 |
| Silvercombe (Management) Limited | Households | 1983 |
| Silverfox Property Solutions Ltd | Real estate | 2012 |
| Silverfox Supplies Limited | Wholesale & retail | 2006 |
| Simon Green Surveying Ltd | Construction | 2025 |
| Simple Bedrooms Ltd | Construction | 2018 |
| Simple Supply Chains Ltd | Administrative & support | 2024 |
| Simplicity Ceremonies Ltd | Extraterritorial | 2024 |
| Simplicity Compliance and Training Solutions(Uk) Ltd | Professional & scientific | 2011 |
| Simply Gadget Solutions Ltd | Other services | 2026 |
| Simply Removals & Storage Ltd | Transport & logistics | 2015 |
| Sinaran (UK) Limited | Hospitality | 2019 |
| Sinclairs Cars Ltd | Transport & logistics | 2025 |
| Singhals Consultancy Ltd | Professional & scientific | 2021 |
| Single PLY Solutions (SW) Ltd | Construction | 2010 |
| SIR Gilbert Scott Court Freehold Company Limited | Households | 2014 |
| Siriuslab Technologies Ltd | Manufacturing | 2026 |
| Siterig Ltd | Information & communication | 2012 |
| Sitesafe (SW) Ltd | Professional & scientific | 2019 |
| SIX Words Speaking Ltd | Professional & scientific | 2025 |
| SJ Plumbing and Heating Limited | Construction | 2014 |
| SJ Surveyors Ltd | Professional & scientific | 2008 |
| SK Boilers and Heating Ltd | Construction | 2024 |
| SK Entertainment Lighting Ltd | Administrative & support | 2018 |
| Skee Projects Limited | Professional & scientific | 2022 |
| Skillsave Ltd | Administrative & support | 2021 |
| Sky High Windows Limited | Administrative & support | 2024 |
| Sky Rascal Fireworks Ltd | Wholesale & retail | 2018 |
| Skybright Roof Windows Ltd | Construction | 2020 |
| SKYLIGHT85 Limited | Transport & logistics | 2021 |
| Slanks Properties Limited | Real estate | 2023 |
| SLS Security Ltd | Administrative & support | 2024 |
| Slspec Ltd | Professional & scientific | 2020 |
| SLW Training & Consultancy Ltd | Education | 2015 |
| SM Babbage Ltd | Construction | 2014 |
| Sm-Rt Consultants Ltd | Wholesale & retail | 2023 |
| Smart Beds Ltd | Manufacturing | 2018 |
| Smart Salvage Ltd | Water & waste | 2025 |
| Smart Solutions 365 Group Ltd | Construction | 2024 |
| Smart Vision Express Ltd | Transport & logistics | 2024 |
| Smarteaze Limited | Professional & scientific | 2014 |
| Smash Ilicious Limited | Hospitality | 2025 |
| SMC Building & Landscapes Ltd | Construction | 2021 |
| Smith Properties WSM Limited | Real estate | 2019 |
| Smithmichael Limited | Manufacturing | 2008 |
| Smiths Hotel WSM Limited | Hospitality | 2022 |
| Smokey Paws Community Interest Company | Professional & scientific | 2015 |
| Smsounds Limited | Arts & recreation | 2015 |
| Snagahome Ltd. | Construction | 2023 |
| Snazzy Sniffers Limited | Other services | 2018 |
| SNI001 Limited | Wholesale & retail | 2012 |
| Snow Lion Security Ltd | Administrative & support | 2019 |
| SNT (South West) Ltd | Wholesale & retail | 2018 |
| SO Davies Group Limited | Financial services | 2017 |
| Sobtrans Ltd | Transport & logistics | 2023 |
| Soccer Shooters (Franchise) Ltd | Education | 2023 |
| Soccer Shooters Ltd | Education | 2018 |
| Social Distancing Solutions Limited | Extraterritorial | 2020 |
| Socks and Sandals Estates Limited | Real estate | 2025 |
| Sodha Care Homes Limited | Health & social care | 2022 |
| Sofacraft Limited | Manufacturing | 2012 |
| Sofos Developments Ltd | Households | 2023 |
| Soft Evolution Ltd | Information & communication | 2021 |
| Software Services Worldwide Ltd | Extraterritorial | 2010 |
| SOL Electrical Services Ltd | Construction | 2024 |
| Sole Revival Consultancy Limited | Health & social care | 2025 |
| Sole Revival Group Limited | Financial services | 2025 |
| Sole Revival Podiatry Limited | Health & social care | 2025 |
| Solelution Limited | Wholesale & retail | 2005 |
| Solo Building and Maintenance Ltd | Construction | 2023 |
| Solo Contractors Ltd | Construction | 2024 |
| Solo Groundworks Ltd | Construction | 2023 |
| Solsbury Court Management (Batheaston) Limited | Households | 1979 |
| Solutions (South West) Limited | Construction | 2006 |