| Shadla Business Solutions Ltd | Professional & scientific | 2025 |
| Shailer GAS Limited | Construction | 2023 |
| Shakerley Consulting Limited | Professional & scientific | 2023 |
| Shannen Dolan Consulting Ltd | Professional & scientific | 2026 |
| Shark Interiors Limited | Construction | 2023 |
| Sharpcomp Limited | Information & communication | 2018 |
| Sherwood's Executive Motors Ltd | Wholesale & retail | 2020 |
| Shivansh Infosystems Limited | Information & communication | 2012 |
| Shoo Enterprise Limited | Transport & logistics | 2016 |
| Shop Unlimited Live Ltd | Other services | 2024 |
| Shortmead Street (Biggleswade) Management Company Limited | Households | 1986 |
| Shuba Consultancy Limited | Professional & scientific | 2021 |
| Sigma Life Limited | Administrative & support | 2021 |
| Sigma Ventilation Systems Ltd | Construction | 2015 |
| Silvercrest Ltd | Real estate | 2023 |
| Silverhind Trading Ltd | Wholesale & retail | 2017 |
| Silverstone Car Sales Ltd | Wholesale & retail | 2020 |
| Simon Levene Productions Limited | Information & communication | 2009 |
| Simon Woodward Ltd | Professional & scientific | 2023 |
| Simpson Properties and Lettings Ltd | Real estate | 2026 |
| Simutec Systems Limited | Information & communication | 2000 |
| Singalong Songs CIC | Arts & recreation | 2014 |
| Sister Motion Limited | Information & communication | 2012 |
| Site Secure Services Limited | Administrative & support | 2018 |
| Sixteen Tons Ltd | Arts & recreation | 2018 |
| SJ Technical - Beds Ltd | Professional & scientific | 2025 |
| SJS Engineering Consultancy Limited | Professional & scientific | 2013 |
| SKILLS4SITE Limited | Construction | 2006 |
| Skin by Anna Ltd | Other services | 2025 |
| Sleek Wheels - UK Ltd | Wholesale & retail | 2023 |
| Slow Rough and Expensive Ltd | Wholesale & retail | 2026 |
| Smart Gadget Store Ltd | Wholesale & retail | 2018 |
| Smart Procurement Solutions Ltd | Professional & scientific | 2020 |
| Smile Locksmith Ltd | Wholesale & retail | 2018 |
| Smith Bernal Holdings Limited | Financial services | 2023 |
| Smith Installations Ltd | Construction | 2022 |
| Smith Myers Communications Ltd | Manufacturing | 1987 |
| Smith Myers Trustees Limited | Professional & scientific | 2023 |
| Smoking GUN Editing Ltd | Information & communication | 2015 |
| Smoothbrush Ltd | Health & social care | 2018 |
| SMV Engineering Ltd | Manufacturing | 2025 |
| Smyth & Co Limited | Professional & scientific | 2007 |
| Smyth Contracting Limited | Construction | 1985 |
| Sneaky Biscuit Ltd | Information & communication | 2016 |
| Snowy Veil Ltd | Wholesale & retail | 2026 |
| SO DE Go Consulting Limited | Wholesale & retail | 2004 |
| Soberstreak AI Ltd | Information & communication | 2026 |
| Soccerlise Football Club Ltd | Arts & recreation | 2020 |
| Soccerlise Ltd | Arts & recreation | 2020 |
| Soft Day Stores Limited | Wholesale & retail | 2024 |
| SOL Safety Management Ltd | Construction | 2016 |
| Solid Oak Media Ltd | Information & communication | 2010 |
| Solina Coatings Holdings Limited | Financial services | 2020 |
| Solina Coatings UK Limited | Manufacturing | 1923 |
| Sollas Bakery Ltd | Manufacturing | 2024 |
| Solo Secure Group Limited | Financial services | 2025 |
| Solo Secure Technologies Limited | Information & communication | 2021 |
| Somerset Soul Trading Ltd | Wholesale & retail | 2021 |
| Songea Ltd | Real estate | 2026 |
| SONIC8 Limited | Wholesale & retail | 2003 |
| Soums Creative Ltd | Professional & scientific | 2023 |
| Sound Recordings Ltd | Manufacturing | 2021 |
| Sound That Media Limited | Information & communication | 2024 |
| Soundtrack Royale Ltd | Arts & recreation | 2022 |
| Southill Tea Rooms Limited | Hospitality | 2025 |
| SPD & Co Property Management Ltd | Real estate | 2024 |
| Spectrum Acoustic Consultants Employee Ownership Trustee Limited | Extraterritorial | 2023 |
| Spectrum Security Solutions Ltd | Construction | 2009 |
| Spirall Ltd | Other services | 2022 |
| Spray Chroma Limited | Construction | 2022 |
| Square Construction Services Limited | Construction | 2017 |
| Square Flag Properties Ltd | Real estate | 2019 |
| SRS Tax LLP | | 2013 |
| SSC Ventures Limited | Construction | 2014 |
| Ssemuyaba Ltd | Information & communication | 2020 |
| Stack Recruitment Ltd | Administrative & support | 2023 |
| Stage-Stars Theatre Academy Ltd | Arts & recreation | 2019 |
| Stairway Entertainment Ltd | Hospitality | 2020 |
| Statecraft Consulting Ltd | Professional & scientific | 2026 |
| Station Road Properties (ST Neots) Limited | Real estate | 1968 |
| Stay Bedford Ltd | Information & communication | 2026 |
| Stay Lifted Ltd | Wholesale & retail | 2019 |
| STE Solutions Limited | Administrative & support | 2012 |
| Stellar Consilium Ltd | Professional & scientific | 2023 |
| Stellar Swan Limited | Professional & scientific | 2025 |
| Step by Step Nursery (Bushey) Ltd | Real estate | 2013 |
| Step by Step Nursery Limited | Education | 2003 |
| Stephanie COX PR Ltd | Information & communication | 2015 |
| Stepping OUT Inns Limited | Hospitality | 2014 |
| Stevens and Sons Roofing Limited | Administrative & support | 2010 |
| Stevens Prestige Limited | Wholesale & retail | 2024 |
| Stevens Roofing Limited | Administrative & support | 2005 |
| STL Power and Process Controls Ltd | Professional & scientific | 1998 |
| Stoneil Limited | Construction | 1997 |
| Stonex Restoration Limited | Administrative & support | 2024 |
| Storm Data Technologies Limited | Information & communication | 2025 |
| Stotfold Engineering Co.Limited | Professional & scientific | 1967 |
| STRIKE6 Limited | Information & communication | 2014 |
| Stronde Limited | Administrative & support | 2015 |
| Stronghold Wood Floors Ltd | Construction | 2021 |