| Sabiedriba AR Ierobezotu Atbildibu "Verne" | | 2005 |
| Sabin Carpentry Ltd | Construction | 2022 |
| Sabre and Fizz Ltd | Hospitality | 2025 |
| Saddex Ltd | Manufacturing | 2011 |
| Safehouse Windows, Doors & Conservatories Limited | Construction | 2013 |
| Safer Wills Limited | Professional & scientific | 2017 |
| Safeteam Training Group Limited | Construction | 2022 |
| Safety Apps Ltd | Information & communication | 2014 |
| Safety Solutions Midlands Ltd | Wholesale & retail | 2005 |
| Safetyhaven Childcare Services Ltd | Education | 2020 |
| Sage + Time Ltd | Administrative & support | 2025 |
| SAI Beauty Parlour Ltd | Other services | 2020 |
| SAI Estate Management Ltd | Real estate | 2020 |
| Saint IVY Management Limited | Professional & scientific | 2018 |
| SAL Corporation Limited | Hospitality | 2018 |
| Salazar Evans Ltd | Health & social care | 2023 |
| Sales Trix Limited | Education | 2023 |
| Saleverywhere Limited | Wholesale & retail | 2015 |
| Salix Associates Limited | Wholesale & retail | 1999 |
| Salixcrafts Limited | Manufacturing | 2013 |
| Salt LAB London Ltd | Wholesale & retail | 2025 |
| Salvation Army Trading Company Limited | Wholesale & retail | 1991 |
| Salvationist Publishing and Supplies Limited | Wholesale & retail | 1917 |
| SAM AI Solutions Ltd | Information & communication | 2023 |
| SAM Currey Plumbing & Heating Ltd | Construction | 2013 |
| Samaita Technologies Ltd | Wholesale & retail | 2024 |
| Samanexus Support Services Ltd | Information & communication | 2026 |
| Sambex IT Limited | Information & communication | 2005 |
| Sambex Limited | Construction | 2012 |
| SAMEDAY247 Courier Ltd | Transport & logistics | 2019 |
| Samson Industrial Doors Limited | Construction | 1998 |
| Samson Outdoor Living Ltd | Wholesale & retail | 2021 |
| Samvex Trading Ltd | Wholesale & retail | 2026 |
| Sandacre Group Limited | Real estate | 2023 |
| Sandacre Property Limited | Real estate | 2023 |
| Sanders Garage Limited | Wholesale & retail | 2003 |
| Santej Limited | Hospitality | 2018 |
| Sapa Developments Ltd | Real estate | 2023 |
| Sapling & Stone Care Limited | Health & social care | 2025 |
| Saracutu Ltd | Manufacturing | 2026 |
| Sarah Loves Cookbooks Limited | Wholesale & retail | 2025 |
| Saramica Clay Limited | Education | 2022 |
| Sarfin Global Solutions Limited | Administrative & support | 2019 |
| Sarira Holdings Limited | Professional & scientific | 2024 |
| Sarira Ltd | Real estate | 2014 |
| Sarotaki Ltd | Professional & scientific | 2019 |
| Sartoris Products Limited | Manufacturing | 1947 |
| Sartoris Property Company Limited | Real estate | 2006 |
| SAS Builder & Construction Limited | Construction | 2023 |
| Saunyama to Clear Limited | Transport & logistics | 2025 |
| SAV & RAJ Ltd | Wholesale & retail | 2012 |
| Savalex Group Limited | Other services | 2025 |
| Savora Tech Ltd | Information & communication | 2026 |
| SB Sparks Ltd | Construction | 2025 |
| SB31 Holdings Limited | Financial services | 2023 |
| Sbeh Ltd | Administrative & support | 2020 |
| SBR Promotions Ltd | Wholesale & retail | 2025 |
| Sbsm Property Management Ltd | Real estate | 2024 |
| SC Food Centre Ltd | Wholesale & retail | 2019 |
| SC Strazile Ltd | Transport & logistics | 2019 |
| SCA London Ltd | Information & communication | 2021 |
| Scaffology Limited | Construction | 2014 |
| Scannerdot Limited | Arts & recreation | 2004 |
| Scas Projects Ltd | Health & social care | 2021 |
| SCC Systems Ltd | Construction | 2024 |
| Schmitz Cabling Limited | Information & communication | 1998 |
| Schoolhaus Limited | Construction | 2013 |
| Sci-Fi Foods Ltd | Manufacturing | 2020 |
| SCL Assessment Ltd | Health & social care | 2025 |
| SCM Motorsport Ltd | Professional & scientific | 2022 |
| Scoala Romaneasca Wellingborough CIC | Education | 2025 |
| Scott Bader Brazil Limited | Professional & scientific | 2013 |
| Scott Bader Commonwealth Limited(The) | Professional & scientific | 1951 |
| Scott Bader Community Fund Trustee Limited | Manufacturing | 1976 |
| Scott Bader Company Limited | Manufacturing | 1923 |
| Scott Bader Exports Limited | Extraterritorial | 1974 |
| Scott Bader Pension Scheme Trustees Limited | Extraterritorial | 2001 |
| Scott Bader UK Limited | Manufacturing | 2002 |
| SCS Haulage Limited | Transport & logistics | 2001 |
| SCW Asset Holdings Ltd | Real estate | 2020 |
| SD O'Hara Transport Ltd | Transport & logistics | 2016 |
| SDG Project Management Ltd | Professional & scientific | 2013 |
| Sdre Limited | Real estate | 2026 |
| SE Management Consultancy Ltd | Professional & scientific | 2020 |
| Sea Fever Travel Limited | Administrative & support | 2025 |
| Seafish Hub Limited | Wholesale & retail | 2024 |
| Seaforth Ivory Holdings Ltd | Health & social care | 2025 |
| Sean Bowen Limited | Construction | 2017 |
| Sean Heath Podiatry Limited | Health & social care | 2023 |
| Sean Mcgowan Limited | Construction | 2008 |
| Sebastian Brychczynski Transport Ltd | Transport & logistics | 2018 |
| Sebastian Property and Investments Ltd | Real estate | 2024 |
| Second Weatherbys Continuation Limited | Extraterritorial | 1982 |
| Secura Cctv Services Ltd | Information & communication | 2026 |
| Secure Consultants (Cambridge) Ltd | Financial services | 2012 |
| Securecpsit Limited | Information & communication | 2025 |
| Secured World Limited | Information & communication | 2017 |
| Securewave Ltd | Information & communication | 2024 |
| Segman Properties Ltd | Real estate | 2020 |
| Seher Furniture Ltd | Wholesale & retail | 2026 |