| Spine Tech Ltd | Health & social care | 2023 |
| Spirit Social Ltd | Professional & scientific | 2025 |
| Splashmaker Media Limited | Professional & scientific | 2023 |
| SPM Distributors Ltd | Wholesale & retail | 2023 |
| Spotlight Property Finance Limited | Financial services | 2020 |
| Spreading the Disease Band Ltd | Information & communication | 2025 |
| Springpod Holdings Inc. | | 2024 |
| Springs Community Limited | Real estate | 2022 |
| SR Super Store Limited | Wholesale & retail | 2016 |
| SRI Balaji Trading Limited | Wholesale & retail | 2020 |
| SRM Contracts Limited | Construction | 2013 |
| SSK Folkestone Limited | Hospitality | 2023 |
| ST Barts Development Limited | Construction | 2020 |
| ST Patricks Road (Deal) Management Company Limited | Households | 2023 |
| ST. Radigunds Community Centre Company | Health & social care | 1999 |
| St.Margaret's Bay Freehold Limited | Real estate | 1999 |
| Stacy Global Trading Ltd | Wholesale & retail | 2024 |
| Standart Resolution Group Ltd | Professional & scientific | 2026 |
| Stanhope Place Management Limited | Households | 2014 |
| Stans Superstore Ltd | Wholesale & retail | 2025 |
| Star of Taiga Ltd | Extraterritorial | 2024 |
| Stark Invest PLC | Extraterritorial | 2024 |
| Staulezo Ltd | Wholesale & retail | 2021 |
| Stef Will FIX IT Ltd | Construction | 2026 |
| Stellina Kitchens Limited | Extraterritorial | 2017 |
| Step Above Safety Limited | Construction | 2018 |
| Stepp Inc. | | 2025 |
| Sterling Architecture Limited | Administrative & support | 2012 |
| Steve Marsh Design Limited | Administrative & support | 2001 |
| Stfd Limited | Professional & scientific | 2025 |
| Still and Always Ltd | Administrative & support | 2019 |
| Stilwell & Singleton LLP | | 2018 |
| Stockley and Turner Ltd | Professional & scientific | 2022 |
| Street Kingz Ltd | Wholesale & retail | 2023 |
| STRENGTH2STRENGTHUK CIC | Health & social care | 2024 |
| Stride Together CIC | Other services | 2026 |
| Strive LTT Ltd | Education | 2015 |
| Structura Software Ltd | Information & communication | 2015 |
| Studio Clic Invest Ltd | Professional & scientific | 2025 |
| Studio Creatif Ltd | Professional & scientific | 2025 |
| Studio Goring Limited | Professional & scientific | 2016 |
| Studio Goring Properties Limited | Real estate | 2025 |
| Sublime Resources Limited | Professional & scientific | 2015 |
| Subrun Limited | Real estate | 2025 |
| Succession Homes Limited | Real estate | 2024 |
| Sullivan & Sons Funeral Service Limited | Other services | 2025 |
| Summer Meadow Management Company Limited | Households | 2023 |
| Sun Sevices Ltd | Health & social care | 2025 |
| Sunburst Pacific Films Limited | Information & communication | 2010 |
| Sunimpress Ltd | Professional & scientific | 2009 |
| Sunset by the Woods Ltd | Hospitality | 2022 |
| Sunset Enterprises Ltd | Transport & logistics | 2021 |
| Sunshine Oriental Ltd | Hospitality | 2026 |
| Super Grill Pizza Ltd | Hospitality | 2024 |
| Supermarine Aviation Works (Vickers) Ltd | Extraterritorial | 2021 |
| Superstocksupply Limited | Wholesale & retail | 2015 |
| Supply My Business Limited | Professional & scientific | 2014 |
| Sure Fired Success Limited | Wholesale & retail | 2020 |
| Susie Fugle Limited | Information & communication | 2003 |
| Sutton Vale Holdings Limited | Financial services | 2019 |
| Suzy Glam Invest Ltd | Extraterritorial | 2023 |
| Suzy Glam Ltd | Extraterritorial | 2023 |
| SWC E-Com Agency Invest Ltd | Wholesale & retail | 2020 |
| Sweatstop Dover Limited | Arts & recreation | 2026 |
| Swellcolnews C.I.C. | Information & communication | 2022 |
| Swip UP Agency Ltd | Information & communication | 2023 |
| Swirlheath Property Management Limited | Professional & scientific | 1993 |
| Swiss Approval NON Destructive Techniques (NDT) Ltd | Professional & scientific | 2015 |
| SWX Creative Limited | Arts & recreation | 2023 |
| System DE MIN Ltd | Manufacturing | 2022 |
| System Synergy Limited | Information & communication | 2002 |
| SZ Assana Ltd | Professional & scientific | 2023 |
| T and T Paving and Groundworks Ltd | Construction | 2023 |
| T Building Services Limited | Construction | 2024 |
| T J Burley Limited | Construction | 2010 |
| T J W Painting & Decorating Limited | Construction | 2023 |
| T L Finishes Limited | Construction | 2014 |
| T.W. Plant Limited | Administrative & support | 2003 |
| Tamara Kitchens PVT Ltd | Wholesale & retail | 2025 |
| Tamoli Renovation Invest Ltd | Extraterritorial | 2024 |
| Tamoli Renovation Ltd | Extraterritorial | 2024 |
| Tankerton Properties Limited | Real estate | 1964 |
| Tawin Holdings Limited | Financial services | 2023 |
| Tax Consulting Services Ltd | Professional & scientific | 2006 |
| Tbnuk Limited | Information & communication | 2022 |
| TC Group Invest Ltd | Professional & scientific | 2022 |
| TCH Solutions Limited | Professional & scientific | 2024 |
| Teaching Ideas Limited | Education | 2014 |
| Team Promosport Ltd | Administrative & support | 2015 |
| Techknowledgies Inc | | 2023 |
| Tee's and Cee's Ltd | Information & communication | 2023 |
| Telegraph Housing Ltd | Administrative & support | 2017 |
| Telmoor Group Ltd | Administrative & support | 2024 |
| Temalcer Property Limited | Real estate | 2023 |
| TEN Marine Parade Limited | Households | 2019 |
| Tesserae HQ Inc. | | 2025 |
| TGT Customs Limited | Wholesale & retail | 2021 |
| Thanet Training and Support Centre Ltd | Administrative & support | 2009 |
| Thapa Foods Ltd | Hospitality | 2024 |
| THE Academy Dover Limited | Arts & recreation | 2019 |