| Saka Group Ltd | Information & communication | 2019 |
| SAL-9000 Ltd | Manufacturing | 2026 |
| Salah Motors Limited | Wholesale & retail | 2026 |
| Salesflo Equipment Limited | Wholesale & retail | 1956 |
| Salisbury Independent Living | Real estate | 2000 |
| SAM FAY Properties Limited | Real estate | 2024 |
| Sample & Patton Limited | Construction | 1997 |
| Samuel's Cafe Ltd | Hospitality | 2024 |
| Samuels Law Limited | Extraterritorial | 2013 |
| Sandcastle Services Limited | Real estate | 2001 |
| Sandstone North West Ltd | Real estate | 2025 |
| Sarann Services Limited | Hospitality | 2025 |
| Sarb Associates Ltd | Health & social care | 2024 |
| Satmo Events Limited | Administrative & support | 2024 |
| Savant (NW) Limited | Administrative & support | 2018 |
| SAZ & J Property Ltd | Real estate | 2024 |
| SB Design Associates Limited | Professional & scientific | 2018 |
| SB Education Services Limited | Construction | 2022 |
| SB GAS (NW) Ltd | Construction | 2019 |
| Scaffold State Limited | Education | 2013 |
| Scalp Styles UK Ltd | Health & social care | 2021 |
| Scantec Personnel Limited | Administrative & support | 1989 |
| Scantec Trustee Limited | Administrative & support | 2024 |
| Scenegraph Studios Ltd | Information & communication | 2017 |
| Scheme 3245 Limited | Information & communication | 2018 |
| Scooters Direct (U.K.) Limited | Extraterritorial | 1999 |
| Scorpio Shelf 2020 Limited | Education | 2020 |
| Scotts (North West) Limited | Wholesale & retail | 2008 |
| Scottsdale Group Limited | Real estate | 2023 |
| Scottsdale Homes Limited | Real estate | 2017 |
| Sculptica Limited | Manufacturing | 2016 |
| Sea Ridge Distillery Ltd | Manufacturing | 2020 |
| Seagull Limited | Wholesale & retail | 1982 |
| Seaking Electrical Limited | Administrative & support | 2001 |
| Seamus Odonnells Limited | Real estate | 2021 |
| Secrcy Ltd | Wholesale & retail | 2026 |
| Secret Garden Neuro Developmental Assessments & Therapies Ltd | Health & social care | 2026 |
| Secure Tech Home Improvements Ltd | Professional & scientific | 2026 |
| Security Express Training N.W. Ltd. | Administrative & support | 2017 |
| Seema Varghese Limited | Health & social care | 2015 |
| Seer Trading Systems Ltd | Information & communication | 2005 |
| Select Takeaways Ltd | Hospitality | 2018 |
| Selltrove Limited | Information & communication | 2026 |
| SEM Education Consultancy Ltd | Professional & scientific | 2024 |
| Sensee (NI) Limited | Administrative & support | 2019 |
| Sensee Financial Services Limited | Financial services | 2014 |
| Sensee Holding Limited | Professional & scientific | 2014 |
| Sensee Ltd. | Administrative & support | 2004 |
| Sensee Operations Limited | Administrative & support | 2024 |
| Sensee Property Services Limited | Real estate | 2024 |
| Seraph Gleam Ltd | Wholesale & retail | 2025 |
| Serenitas Property Ltd | Real estate | 2025 |
| Serenity Sun Creams Limited | Other services | 2026 |
| Service Engineering Marine Limited | Professional & scientific | 1999 |
| Sevenoaks Management Company (NO. 1) Limited | Households | 2009 |
| Severnside Foods Limited | Extraterritorial | 1995 |
| Seymore Lowe Developments Limited | Construction | 2021 |
| Seymore Lowe Ltd | Professional & scientific | 2019 |
| Seymore Lowe Properties Limited | Real estate | 2020 |
| SFD Services Ltd | Professional & scientific | 2021 |
| SGG Environmental Solutions Limited | Water & waste | 2018 |
| SH Building & Electrical Ltd | Construction | 2022 |
| SH Rigging Services Limited | Construction | 2017 |
| Shamrock Group Ltd | Professional & scientific | 2025 |
| Shamrock NDT & Integrity Services Ltd | Professional & scientific | 2026 |
| Shannock Girl Ltd | Arts & recreation | 2019 |
| Sharneywood Limited | Hospitality | 1980 |
| Shawarma Fresh Birkenhead Ltd | Hospitality | 2026 |
| Shayan Phone Store Limited | Wholesale & retail | 2025 |
| SHE Said Productions Ltd | Other services | 2015 |
| SHG Engineering NW Ltd | Other services | 2013 |
| SHG Technical Services Ltd | Manufacturing | 2022 |
| Shield Door Protect Ltd | Other services | 2021 |
| Shieldwall Outdoor Limited | Manufacturing | 2017 |
| SHOP162 Ltd | Wholesale & retail | 2025 |
| Shopaim International Ltd | Wholesale & retail | 2022 |
| Shortlist Consulting Limited | Administrative & support | 2020 |
| Shortlist Holdings Limited | Administrative & support | 2020 |
| Shortlist Recruitment Limited | Administrative & support | 2012 |
| Shrewsbury View Freehold Company Limited | Households | 2006 |
| Shyne Pro Cleaning Ltd | Administrative & support | 2025 |
| SIA Barbers Birkenhead Limited | Other services | 2024 |
| Siam Golden 888 Thai Massage and Spa Ltd | Other services | 2019 |
| Siena CH42 Ltd | Hospitality | 2026 |
| Sigma Business Finance Ltd | Financial services | 2024 |
| Silica Estates Limited | Real estate | 2018 |
| Silver Comp Ltd | Manufacturing | 2025 |
| Silver FOX Business Solutions Ltd | Other services | 2019 |
| Silverdale CNT Holdings Ltd | Real estate | 2021 |
| Silverstone Advisory Ltd | Information & communication | 2022 |
| Simmons Orthopaedics Limited | Health & social care | 2008 |
| Simon Harper Music Ltd | Education | 2018 |
| Simon M Graham Medical Ltd | Health & social care | 2017 |
| Simple Credit Limited | Financial services | 2005 |
| Simple Lighting Ltd | Wholesale & retail | 2019 |
| Simplefix (Letter Fixings) Limited | Extraterritorial | 2014 |
| Simply Auto Repairs Ltd | Wholesale & retail | 2026 |
| Simply Debonair Dogs (Prenton) Limited | Other services | 2018 |
| Simply Made Sourcing Ltd | Real estate | 2023 |
| Sinclair Goldberg Price Limited | Financial services | 2000 |