| Stonebridge 25 Limited | Real estate | 2018 |
| Stoneham Workshops Limited | Real estate | 2018 |
| Stonehaven Tradeworks Ltd | Wholesale & retail | 2025 |
| Stonesfield Leather Limited | Wholesale & retail | 2020 |
| Stony Bakers Limited | Hospitality | 2024 |
| Stony Capital Ltd | Financial services | 2022 |
| Stony Express Ltd | Wholesale & retail | 2025 |
| Stony Express SK Ltd | Wholesale & retail | 2026 |
| Stony Holding Co Ltd | Financial services | 2025 |
| Stony Lounges Management Limited | Hospitality | 2021 |
| Stony Microworks Ltd | Information & communication | 2010 |
| Stony Properties Ltd | Real estate | 2016 |
| Stony Property Limited | Administrative & support | 2019 |
| Stony Radio CIC | Information & communication | 2020 |
| Stony Restaurant Limited | Hospitality | 2020 |
| Stony Stratford Autos Ltd | Wholesale & retail | 2022 |
| Stony Stratford Bowls Club Limited | Arts & recreation | 2024 |
| Stony Stratford Builders Limited | Real estate | 1976 |
| Stony Stratford Croquet Club | Arts & recreation | 2024 |
| Stony Stratford Lawn Tennis Club Limited | Arts & recreation | 2024 |
| Stony Stratford Stores Limited | Wholesale & retail | 2007 |
| Stony Stratford Town Football Club CIC | Arts & recreation | 2024 |
| Stony's Chicken Ltd | Hospitality | 2026 |
| Stop BOT Ltd | Manufacturing | 2021 |
| Stopcocks Maintenance Ltd | Construction | 2017 |
| Storage Essentials Limited | Wholesale & retail | 2006 |
| Storage MK Limited | Transport & logistics | 2014 |
| Store 212 Ltd | Real estate | 2026 |
| Store Away Engineering Limited | Professional & scientific | 2022 |
| Storey Family Investment Company | Other services | 2019 |
| Storey Property Developments (One) Limited | Real estate | 2018 |
| Storey Property Developments (Two) Limited | Real estate | 2018 |
| Storing Cars Limited | Other services | 2022 |
| Storm Entrepreneurial Academy CIC | Education | 2025 |
| Storm Gadgets Ltd | Wholesale & retail | 2010 |
| Storm IT Solutions Limited | Information & communication | 2020 |
| Storm Office Limited | Manufacturing | 2011 |
| Storm Office Solutions Limited | Administrative & support | 2015 |
| Storm Selection Limited | Administrative & support | 2005 |
| Stormwise Ltd | Professional & scientific | 2021 |
| Story Art Ltd | Wholesale & retail | 2004 |
| Storyboard Limited | Wholesale & retail | 2005 |
| Storypoints AI Limited | Information & communication | 2024 |
| Stotfold Football Club | Arts & recreation | 2016 |
| Stowaway Services Limited | Transport & logistics | 2016 |
| Stowfledge (Manufacturing) Limited | Manufacturing | 2018 |
| Stowhill Developments Limited | Construction | 2018 |
| Stra Services Ltd | Professional & scientific | 2026 |
| Stracomer Services Ltd | Administrative & support | 2008 |
| Stradivarius Group Ltd | Financial services | 2025 |
| Straight Claims Ltd | Wholesale & retail | 2026 |
| Strainsense Limited | Wholesale & retail | 2002 |
| Stralite Ltd | Manufacturing | 2018 |
| Straquatis Ltd | Wholesale & retail | 2014 |
| Strat's MK Limited | Hospitality | 2026 |
| Stratebiz Solutions Limited | Information & communication | 2015 |
| Strategic Communications Inc (UK) Limited | Administrative & support | 2018 |
| Strategic Marketing Coach Limited | Hospitality | 2016 |
| Strategic Simulation and Analysis Limited | Extraterritorial | 2007 |
| Strategiv Limited | Professional & scientific | 2024 |
| Strategx Ltd | Extraterritorial | 2025 |
| Strategy OT Limited | Professional & scientific | 2018 |
| Stratford & Stratford Properties Limited | Real estate | 2004 |
| Stratford Autos Ltd | Wholesale & retail | 2025 |
| Stratford House Ltd | Health & social care | 2018 |
| Stratford Office Village Management Company Limited | Households | 2003 |
| Stratford Park (Wolverton) Management Company Limited | Households | 2012 |
| Stratford Park Stores Limited | Wholesale & retail | 2015 |
| Stratford Services & Maintenance Limited | Manufacturing | 2017 |
| Stratfords DRY Cleaners (Stony) Ltd | Other services | 2025 |
| Stratfords Executive Cars Limited | Transport & logistics | 2005 |
| Stratfords Motorist Centre Limited | Wholesale & retail | 2004 |
| Stratix Consulting Ltd | Information & communication | 2025 |
| Stratonex Defence Technologies Ltd | Professional & scientific | 2026 |
| Stratovate Technologies Limited | Information & communication | 2025 |
| Stratsys IT Solutions Ltd | Information & communication | 2025 |
| Stratton Utilities Limited | Energy | 2022 |
| Stratum Capital Advisory Limited | Information & communication | 2026 |
| Stratum Land & Capital Ltd | Real estate | 2026 |
| Strava Cafe Ltd | Hospitality | 2024 |
| Strawberry Consultancy Ltd | Administrative & support | 2025 |
| Strawberry Fields (UK) Limited | Information & communication | 2002 |
| Strawberry Sports Management Ltd | Arts & recreation | 2016 |
| Streamspace Ltd | Information & communication | 2024 |
| Streamverge Limited | Hospitality | 1983 |
| Street Ministers Limited | Other services | 2011 |
| Street Monkeys North West Limited | Arts & recreation | 2019 |
| Streetlaight Ltd | Other services | 2024 |
| Streets Metal Limited | Water & waste | 2014 |
| Streetworks Consultancy Ltd | Construction | 2025 |
| Strenco Tools Limited | Manufacturing | 1991 |
| Stretch Academy Ltd | Professional & scientific | 2019 |
| Stretch TOO Property Ltd | Real estate | 2018 |
| Stretchview Limited | Information & communication | 2023 |
| Stretton West Limited | Financial services | 2025 |
| Strictly Music Limited | Manufacturing | 2010 |
| Strictly Property Ltd | Real estate | 2016 |
| Strider IT Solutions Limited | Wholesale & retail | 2020 |
| Strideshub Limited | Information & communication | 2024 |
| Striking Accounts Ltd | Professional & scientific | 2024 |