| SEL Highway Specialists Ltd | Construction | 2025 |
| Selling Activities Fundraising & Events Company Ltd | Administrative & support | 2024 |
| Senda Movement Limited | Agriculture & fishing | 2023 |
| Sequoia Systems (Kent) Limited | Agriculture & fishing | 2022 |
| Serenity Concept Ltd | Wholesale & retail | 2022 |
| Serenity Faversham Ltd | Other services | 2019 |
| Serve UP Padel Ltd | Arts & recreation | 2025 |
| Sharpe Contractors Ltd | Information & communication | 2009 |
| Sheldwich Primary School | Education | 2011 |
| Sheldwich Village Events Management Company | Health & social care | 2013 |
| Shepherd Advisory Partners LLP | | 2024 |
| Shipway Price Limited | Real estate | 2017 |
| Shiv&Sons Limited | Wholesale & retail | 2025 |
| Shwen Shwen Limited | Wholesale & retail | 2020 |
| Sidell Limited | Professional & scientific | 2016 |
| Sigurdsson Investments Limited | Real estate | 2020 |
| Silvercrest Property Corporation Limited | Construction | 1992 |
| Silverkey Property Sourcing Ltd | Administrative & support | 2016 |
| Silverman Capital Ltd | Financial services | 2020 |
| Simcig Ltd | Wholesale & retail | 2014 |
| Simms International PLC | Wholesale & retail | 1991 |
| Simon Paul Gardens Limited | Administrative & support | 2019 |
| Sipsys Limited | Information & communication | 2006 |
| Siraa Ltd | Other services | 2017 |
| Sitti Decorators Ltd | Construction | 2015 |
| Sittingbourne and District Motorcycle Club Limited | Arts & recreation | 2007 |
| Sittingbourne Cabs Limited | Transport & logistics | 2016 |
| SIX Blue Ltd | Information & communication | 2019 |
| Sjbhq Ltd | Information & communication | 2026 |
| SJR Electrical Solutions Ltd | Construction | 2020 |
| SJS (Kent) Limited | Agriculture & fishing | 2023 |
| SK & G Limited | Other services | 2016 |
| Skabardis Marine Carpentry Ltd | Construction | 2012 |
| Slams Limited | Hospitality | 2023 |
| SM Sims Ltd | Wholesale & retail | 2016 |
| Smart Wire Approved Electricians Limited | Construction | 2013 |
| Smithwick Ltd | Construction | 2015 |
| SMS Creative Services Limited | Arts & recreation | 2011 |
| SNAP2 Limited | Information & communication | 2023 |
| Snape Farms Limited | Agriculture & fishing | 1996 |
| SO Smart Media Limited | Arts & recreation | 1999 |
| Social Research & Practice and Education Ltd | Professional & scientific | 2020 |
| Society of Later Life Advisers | Financial services | 2008 |
| Soles Hill Farm Limited | Agriculture & fishing | 1982 |
| Solid Katering Limited | Other services | 2017 |
| Solla Enterprises Limited | Financial services | 2013 |
| Solly-Kenji Ltd | Transport & logistics | 2026 |
| Solros Occupational Therapy Ltd | Health & social care | 2025 |
| Solstice House Faversham Ltd | Other services | 2026 |
| Somnus Properties Ltd | Real estate | 2026 |
| Sondes Court Residents Company Limited | Administrative & support | 2013 |
| Sophie Bell & Associates Ltd | Other services | 2020 |
| South East and London Landscapes Ltd | Professional & scientific | 2025 |
| South East Building Company Limited | Construction | 1984 |
| South Eastern Transport Limited | Transport & logistics | 2010 |
| South Hill Farm Smallholding Ltd | Agriculture & fishing | 2023 |
| Southeast Lofts Kent Ltd | Construction | 2025 |
| Southern Computer Services Limited | Information & communication | 1997 |
| Southwick Solar Limited | Energy | 2013 |
| Sovereign Freight Limited | Transport & logistics | 2016 |
| Sovex Developments Limited | Agriculture & fishing | 1986 |
| Space & Storage Limited | Transport & logistics | 2020 |
| Space Saver Storage Limited | Real estate | 1996 |
| Spaced Agency Ltd | Information & communication | 2022 |
| Speakman Sound Ltd. | Information & communication | 2013 |
| Specialist in Land Condition Register Limited | Other services | 2011 |
| Spice Lounge Indian Restaurant Ltd | Hospitality | 2024 |
| Spice of Life Faversham Ltd | Hospitality | 2025 |
| Spitfire Business Park Limited | Construction | 2018 |
| Spitfire Developments Limited | Construction | 2018 |
| Sports Connect Community CIC | Education | 2021 |
| Sports Connect UK Ltd | Arts & recreation | 2019 |
| SPR Tradein Ltd | Wholesale & retail | 2024 |
| ST Buildings (Kent) Ltd | Construction | 2012 |
| ST. George's (South East) Limited | Professional & scientific | 2010 |
| ST. Mary Court Residents Society Limited | Households | 1982 |
| Stalisfield Equine Centre Limited | Construction | 2008 |
| Stanford & Green Limited | Administrative & support | 2003 |
| Stanton Arch Construction Consultants Ltd | Construction | 2015 |
| Stanton Arch Property Ltd | Real estate | 2021 |
| Starcrown Services Ltd | Professional & scientific | 1996 |
| Stark Systems Engineering Ltd | Professional & scientific | 2025 |
| Stationguru Limited | Professional & scientific | 2022 |
| Stellingwood Ltd | Real estate | 2023 |
| Stepperlane Limited | Real estate | 1979 |
| Stoaty Properties Ltd | Real estate | 2024 |
| Stolz Consulting Ltd | Real estate | 2017 |
| Stone Management Services Ltd. | Administrative & support | 2021 |
| Stone Security Ltd. | Administrative & support | 2011 |
| Stonebridge Building Consultancy Limited | Professional & scientific | 2024 |
| Stonegate House Limited | Real estate | 2017 |
| Stones Advanced Scaffolding & Inspection Services Ltd | Construction | 2018 |
| Stratton Hall Farms (Holdings) Limited | Professional & scientific | 2011 |
| Stratton Hall Farms Limited | Agriculture & fishing | 2010 |
| Street Sustainables Ltd | Wholesale & retail | 2020 |
| Stripey Lizard Creative Services Ltd | Construction | 2015 |
| Stripey Monkey Creative Services Ltd | Arts & recreation | 2015 |
| Structured Trading Limited | Administrative & support | 1998 |
| Stubbs Pubs Limited | Hospitality | 2024 |
| Studio Nova AS Limited | Professional & scientific | 2020 |