| Ryjo Homes Ltd | Real estate | 2025 |
| Ryran Ltd | Construction | 2024 |
| RÉ Suncare Ltd | Wholesale & retail | 2020 |
| S & D Construction Partnership Limited | Professional & scientific | 2026 |
| S & T Private Hire Ltd | Transport & logistics | 2018 |
| S B Interiors Limited | Construction | 2002 |
| S C Transport Consultancy Ltd | Professional & scientific | 2019 |
| S D Installers Limited | Construction | 2018 |
| S Harris Consulting Ltd | Information & communication | 2017 |
| S L E Accountancy & Bookkeeping Limited | Professional & scientific | 2022 |
| S L Ecology Limited | Professional & scientific | 2024 |
| S L Jones Automotive Ltd | Wholesale & retail | 2025 |
| S Tilson Building Limited | Construction | 2014 |
| S X Training Ltd | Administrative & support | 2010 |
| S&D Sushi UK Limited | Hospitality | 2023 |
| S&J Food Beverage Ltd | Wholesale & retail | 2022 |
| S&M Auto Services Ltd | Wholesale & retail | 2021 |
| S&W Capital Limited | Financial services | 2020 |
| S.D Higgins Limited | Professional & scientific | 2008 |
| S.G. Butcher Limited | Construction | 1997 |
| S.G.Electrics Limited | Construction | 1990 |
| S.J. Ashley Consulting Limited | Professional & scientific | 2005 |
| S.J.P Supplies Limited | Wholesale & retail | 2026 |
| S.R.V.Niro Ltd | Hospitality | 2025 |
| S11 Coaching Ltd | Administrative & support | 2026 |
| S6 Environmental Ltd | Water & waste | 2024 |
| S7 Business Development Ltd | Administrative & support | 2020 |
| Sabco Holdings Ltd | Financial services | 2025 |
| Sadiq Ltd | Health & social care | 2021 |
| Safe FIX GAS & Property Limited | Energy | 2025 |
| Safe Haven Services Limited | Hospitality | 2018 |
| Safeserve Limited | Real estate | 1992 |
| Safety Search Recruitment Limited | Administrative & support | 2003 |
| Saffa Car Leasing Limited | Extraterritorial | 2018 |
| Safwat Cars Limited | Wholesale & retail | 2005 |
| Sage Infrastructure Limited | Real estate | 2017 |
| Sagewell Health Limited | Wholesale & retail | 2025 |
| Saks Canvey Limited | Hospitality | 2022 |
| Saks Southend Limited | Hospitality | 2022 |
| Sakura Racing Ltd | Wholesale & retail | 2022 |
| SALALIMA4 Limited | Health & social care | 2024 |
| SALES888 Ltd | Wholesale & retail | 2024 |
| Salisbury Court Properties Limited | Households | 1990 |
| Salon by ME Limited | Other services | 2026 |
| Salonvip by Yasin Mimar Ltd | Other services | 2019 |
| Saloon Clothing Limited | Wholesale & retail | 2025 |
| Saltaire Limited | Professional & scientific | 2020 |
| Salvation View Management Limited | Extraterritorial | 2021 |
| Samirs Catering Ltd | Hospitality | 2018 |
| Samos Sun Ltd | Wholesale & retail | 2025 |
| Sampson & Leigh Limited | Wholesale & retail | 2024 |
| Samtaf Services Ltd | Education | 2026 |
| Samuel Higgins Ltd | Professional & scientific | 2026 |
| Sanaa Food Service Ltd | Hospitality | 2019 |
| Sancto Limited | Wholesale & retail | 2008 |
| Sanderox Limited | Manufacturing | 2012 |
| Sandom Kirby Associates Ltd | Financial services | 2017 |
| Sandringham Road Freehold Ltd | Administrative & support | 2017 |
| Sandum Property Limited | Real estate | 2017 |
| Santi Enterprises Limited | Professional & scientific | 2014 |
| Sanz Legal Services Ltd | Professional & scientific | 2024 |
| Sapphire Court Management Company Limited | Real estate | 1996 |
| Saradhi Estates Limited | Real estate | 2023 |
| Sarah Jane Baker Limited | Health & social care | 2023 |
| Sarah's Creative Chocolate Kitchen Limited | Hospitality | 2016 |
| Sarl Limited | Hospitality | 2024 |
| Sarla Devi & Grandson Ltd | Real estate | 2024 |
| Sarn Properties Limited | Administrative & support | 2017 |
| Sash Stoma Belts Limited | Manufacturing | 2020 |
| Saturn Plumbing and Heating Limited | Construction | 2003 |
| Saucykipper Ltd | Professional & scientific | 2021 |
| Sauteurs (ST Patricks) Limited | Other services | 2023 |
| Savalex Limited | Wholesale & retail | 2017 |
| Saxon Walk Residents Company Limited | Households | 2003 |
| Sazzad & Riva Properties Ltd | Real estate | 2024 |
| SBM Care Ltd | Health & social care | 2015 |
| SBP Enterprises Limited | Real estate | 2019 |
| SC Distributionss Ltd | Wholesale & retail | 2025 |
| SC Elite Capital Ltd | Financial services | 2023 |
| Scaena Limited | Arts & recreation | 2021 |
| Scalepath Engineering Advisory Ltd | Information & communication | 2026 |
| Scan Group Holding Limited | Manufacturing | 2005 |
| Scandecon Limited | Administrative & support | 2023 |
| Scarlett Montanaro Ltd | Professional & scientific | 2024 |
| SCB Landscaping Limited | Administrative & support | 2015 |
| SCC Domestic Plumbing and Heating Limited | Construction | 2014 |
| Scendr Ltd | Administrative & support | 2023 |
| Scents of Terra Ltd | Wholesale & retail | 2025 |
| Sceptre Finance Limited | Financial services | 2001 |
| Scitum Limited | Information & communication | 2012 |
| Sciv Limited | Real estate | 2025 |
| Scoops 37 Limited | Wholesale & retail | 2023 |
| Scorpions Basketball Limited | Arts & recreation | 2022 |
| Scotkeyne Limited | Extraterritorial | 1977 |
| Scott House Management (Leigh on Sea) Limited | Households | 1990 |
| SCR International Ltd | Administrative & support | 2017 |
| Scragg Financial Services Limited | Financial services | 2016 |
| Scrivs Sealants Limited | Construction | 2021 |
| SCX Medical Ltd | Manufacturing | 2019 |
| SD Chattels Ltd | Wholesale & retail | 2013 |