| Sunbreeze Limited | Transport & logistics | 2017 |
| Sungava Ltd | Hospitality | 2020 |
| Sunny Chips Shop Ltd | Hospitality | 2017 |
| Sunup Energy Limited | Construction | 2025 |
| Super Basic Limited | Information & communication | 2025 |
| Super Cheap Autos Ltd | Wholesale & retail | 2025 |
| Super Function Ltd | Information & communication | 2013 |
| Super Mini Market Ltd | Wholesale & retail | 2015 |
| Super Vision Clinic Ltd | Health & social care | 2023 |
| Superb Music Ltd | Information & communication | 2015 |
| Superfoil Installations Ltd | Manufacturing | 2026 |
| Superlincs LN Limited | Manufacturing | 2019 |
| Supplements for Sport Limited | Hospitality | 2011 |
| Supply to U Limited | Wholesale & retail | 2018 |
| SURE360 Limited | Information & communication | 2017 |
| Surepave Groundworks Ltd | Construction | 2025 |
| Surface Repair Lincoln Ltd | Construction | 2017 |
| Surrey and Sussex Surgical Ltd | Health & social care | 2018 |
| Surrey Medical Consultancy Ltd | Health & social care | 2013 |
| Surrey Orthopaedic Clinic LLP | | 2011 |
| Surrey Pain Management Services Ltd | Health & social care | 2011 |
| Surveyline Geomatics UK Ltd | Professional & scientific | 2020 |
| Susan Jacklin Ltd | Health & social care | 2023 |
| Sustainability on Call Ltd | Professional & scientific | 2026 |
| Sustainable Water Innovations Ltd | Water & waste | 2024 |
| Sustex Ltd | Wholesale & retail | 2026 |
| Sutton Castings Limited | Manufacturing | 2019 |
| Sven Knee Ltd | Health & social care | 2023 |
| Sven SKI Clinic Ltd | Health & social care | 2025 |
| Svojas Limited | Wholesale & retail | 2017 |
| Svojas Properties Limited | Real estate | 2019 |
| SVP Travel Ltd | Administrative & support | 2023 |
| Svreiign Ltd | Financial services | 2025 |
| Svreiign Sports Ltd | Arts & recreation | 2025 |
| Svreiign Studios Ltd | Professional & scientific | 2025 |
| SVS Specialist Drivers Limited | Transport & logistics | 2018 |
| Svva Ltd | Transport & logistics | 2014 |
| SW Engineering Contractors (Lincoln) Ltd | Professional & scientific | 2024 |
| SW Engineering Ltd | Professional & scientific | 2016 |
| SW Event Management Ltd | Administrative & support | 2024 |
| SW Renewables Ltd | Information & communication | 2017 |
| Swains Holiday Lets Ltd | Hospitality | 2020 |
| Swallow Cleaning Contractors Limited | Other services | 2003 |
| Swan House Investments Limited | Professional & scientific | 2006 |
| Swan Street Apartments Limited | Real estate | 2003 |
| Swanholme Materials Ltd | Wholesale & retail | 2022 |
| Swann Lighting Limited | Manufacturing | 2014 |
| Swdg Limited | Professional & scientific | 2015 |
| Sweet Shop (Tattershall) Limited | Wholesale & retail | 2017 |
| Sweetdoughthings Ltd | Manufacturing | 2020 |
| Sweetmilk Limited | Information & communication | 2013 |
| Sweetpea Active Ltd | Wholesale & retail | 2025 |
| Swell Property Management Ltd | Real estate | 2025 |
| Swift Community Events Limited | Arts & recreation | 2026 |
| Swift Global Events Limited | Manufacturing | 2022 |
| Swift Writing Services Ltd | Professional & scientific | 2025 |
| SWIFT28 Ltd | Wholesale & retail | 2026 |
| Swiftbuilt Construction Ltd | Construction | 2025 |
| Swiftoak Global Trading Ltd | Wholesale & retail | 2026 |
| Swiftpoint Solutions Ltd | Water & waste | 2026 |
| Swim Days Lincolnshire Limited | Arts & recreation | 2022 |
| Swinderby Construction Limited | Construction | 2014 |
| Switchup Marketing Ltd | Professional & scientific | 2026 |
| SY Resources Ltd | Information & communication | 2021 |
| Sycis Group Ltd | Other services | 2022 |
| Sycis Limited | Information & communication | 2005 |
| Syed & Quinn Limited | Education | 2000 |
| Syed Ventures Ltd | Wholesale & retail | 2026 |
| Sykes Farm Investments Ltd | Professional & scientific | 2024 |
| Sykes Lincoln Limited | Professional & scientific | 2008 |
| Sykes Properties Limited | Real estate | 2003 |
| Sykes Video Links Ltd | Wholesale & retail | 1986 |
| Symphony Hair Studio Ltd | Other services | 2023 |
| Syncopated Sound Co Limited | Arts & recreation | 2002 |
| Synergi Tech (IP) Limited | Information & communication | 2015 |
| Synergi Tech Group Limited | Administrative & support | 2011 |
| Synergi Tech Limited | Information & communication | 2013 |
| Synergie-Cad (UK) Limited | Manufacturing | 2000 |
| Synergy Autocentres Coventry Ltd | Wholesale & retail | 2025 |
| Synergy Autocentres Lincoln Ltd | Wholesale & retail | 2024 |
| Synergy Sports Coaching Limited | Arts & recreation | 2015 |
| Synergy Technology Group Ltd | Administrative & support | 2017 |
| Synoveus Ltd | Financial services | 2019 |
| Synthetic Limited | Extraterritorial | 2015 |
| Synvolve Limited | Professional & scientific | 2025 |
| Synx Games Ltd | Information & communication | 2022 |
| Syslink Limited | Real estate | 1986 |
| System Servicing Limited | Construction | 2026 |
| Systemfinity Ltd | Information & communication | 2022 |
| Systemfinity Studios Ltd | Information & communication | 2024 |
| Syzygy Records Ltd | Information & communication | 2025 |
| T & C Shaw Ltd | Construction | 2018 |
| T & J Leisure Ltd | Hospitality | 2012 |
| T & J Properties Lincoln Ltd | Financial services | 2022 |
| T & L Compliance Services Limited | Professional & scientific | 2026 |
| T & R Hawley Ltd | Financial services | 2021 |
| T & S Netting Solutions Limited | Construction | 2013 |
| T and L Hounsfield Limited | Financial services | 2020 |
| T C Motors (Lincoln) Limited | Wholesale & retail | 2006 |
| T Crowe Ltd | Construction | 2015 |