| Scenic King Ltd | Professional & scientific | 2022 |
| Scentnova Ltd | Wholesale & retail | 2024 |
| Scentstation Vending Machines Ltd | Wholesale & retail | 2025 |
| Schiopu Ltd | Construction | 2022 |
| Schiopu Silviu Ltd | Transport & logistics | 2024 |
| Schneider Properties Limited | Real estate | 2023 |
| School Business & Finance Services (UK) Limited | Professional & scientific | 2019 |
| School Holiday Camps Ltd | Health & social care | 2023 |
| School Lane Mortgages Ltd | Financial services | 2019 |
| School Wrap Ltd | Health & social care | 2018 |
| Schpark Ltd | Administrative & support | 2023 |
| Schumacher Racing Holdings Limited | Manufacturing | 2020 |
| Schumacher Racing Products Limited | Manufacturing | 1987 |
| Science Intervention Centre Ltd | Education | 2022 |
| Scientific Instruments Limited | Manufacturing | 2012 |
| Scissor & Razor Ltd | Other services | 2024 |
| SCJ Events Limited | Hospitality | 2022 |
| SCL Electrical and Energy Limited | Construction | 2009 |
| SCN Construction Ltd | Construction | 2026 |
| Scoble Limited | Administrative & support | 2006 |
| Scoobys Doggy Day Care & Spa Northampton Ltd | Other services | 2025 |
| Scooster Media Limited | Information & communication | 2026 |
| Scope Design UK Ltd | Construction | 2020 |
| Scorewell Solutions Limited | Information & communication | 2005 |
| Scorpion Connections Limited | Financial services | 2005 |
| Scorpion Music Group Limited | Information & communication | 2023 |
| Scorpion Property Limited | Real estate | 2018 |
| Scorpion Security Guarding Services Limited | Administrative & support | 1993 |
| Scorpion Team Ltd | Transport & logistics | 2026 |
| Scorpions K-9 Security Service Ltd | Administrative & support | 2025 |
| Scorylo Ltd | Transport & logistics | 2018 |
| Scot Bennett Engineering Limited | Manufacturing | 1999 |
| Scots Consulting Limited | Other services | 2012 |
| Scott Brown Olney Limited | Other services | 2016 |
| Scott Carthy Limited | Arts & recreation | 2026 |
| Scott Marshall Building Services Ltd | Construction | 2023 |
| Scott Murray Restaurants Ltd | Hospitality | 2019 |
| Scott Rodriguez Consulting Limited | Professional & scientific | 2020 |
| Scott Soranut Zelinsky Ltd | Extraterritorial | 2024 |
| Scotts Recovery Ltd | Wholesale & retail | 2022 |
| SCR Logistic Ltd | Transport & logistics | 2020 |
| Scraffs Limited | Wholesale & retail | 2016 |
| Scraptoft Hall RTM Company Limited | Households | 2020 |
| Screen Edge Limited | Manufacturing | 2016 |
| Screen Northants Alternative Provision Ltd | Education | 2026 |
| Screen Northants Limited | Information & communication | 2015 |
| Screenworks (Europe) Limited | Administrative & support | 2000 |
| Screwpoint Ltd | Wholesale & retail | 2023 |
| Scrivenger Seabrook Limited | Professional & scientific | 2010 |
| Scroll Labs Ltd | Wholesale & retail | 2025 |
| Scroxton & Partners Ltd | Professional & scientific | 2009 |
| Scrubbingtons Ltd | Wholesale & retail | 2024 |
| SCS Build Limited | Other services | 2025 |
| SCS Solution Cleaning Ltd | Administrative & support | 2024 |
| SCT Financial Consultancy Limited | Professional & scientific | 2025 |
| Scuffed Productions Ltd | Information & communication | 2020 |
| Sculpt Northampton Ltd | Other services | 2024 |
| Sculptorvj Limited | Construction | 2023 |
| Scyphus Ltd | Manufacturing | 2009 |
| SD Carpentry (Wboro) Limited | Construction | 2005 |
| SD11 Ltd | Transport & logistics | 2021 |
| SDB Properties Limited | Construction | 1995 |
| SDB Property Developments Ltd | Construction | 2020 |
| SDC Solutions Ltd | Real estate | 2026 |
| SDH Projects Ltd | Construction | 2024 |
| SDJ Carpentry & Landscaping Ltd | Construction | 2026 |
| SDM Accounting Limited | Professional & scientific | 2005 |
| SDM Educational Limited | Education | 2014 |
| SDM Powered Access Limited | Manufacturing | 2022 |
| SDN Holdings Limited | Financial services | 2022 |
| SDQ Consulting Limited | Information & communication | 2025 |
| SDQ Peer Ltd | Hospitality | 2025 |
| SDS Operations Ltd | Professional & scientific | 2018 |
| SE Art Retain Walls Ltd | Construction | 2024 |
| Sea Wave Properties Limited | Real estate | 2024 |
| Seaa Construction Ltd | Construction | 2021 |
| Seafetcher Data Consult Limited | Health & social care | 2024 |
| Seaght Ltd | Information & communication | 2024 |
| Sealfit Active Training Ltd | Transport & logistics | 2025 |
| Sealsense Ltd | Manufacturing | 2022 |
| Seamark Technical Solutions Ltd | Construction | 2026 |
| Seamount Global Ltd | Financial services | 2025 |
| Sean Cooksley Design Limited | Professional & scientific | 2018 |
| Sean Fitzsimons Contracting Ltd | Construction | 2025 |
| Search IT Local Media (UK) Limited | Professional & scientific | 2024 |
| Sears House Management Company Limited | Households | 1991 |
| Seaside Stays Ltd | Real estate | 2022 |
| Season & Vine Ltd | Professional & scientific | 2008 |
| Seasons of Wealth Ltd | Financial services | 2018 |
| Seaview Fitness Limited | Arts & recreation | 2009 |
| Seaview Vista Limited | Real estate | 2021 |
| Sebadent Limited | Health & social care | 2017 |
| Sebastian Art Limited | Arts & recreation | 2016 |
| Sebatall Construction Management Limited | Construction | 2016 |
| SEC Energy Ltd | Construction | 2024 |
| SEC Manufacturing Limited | Manufacturing | 2016 |
| Seca Properties Ltd | Real estate | 2024 |
| Secjust Ltd | Professional & scientific | 2025 |
| Seckington Homes Ltd | Households | 2025 |
| Seckingtons Limited | Other services | 2011 |