| Staward Advisory Ltd | Professional & scientific | 2021 |
| Stay Posted Marketing Limited | Information & communication | 2026 |
| Stay Pro+ Ltd | Hospitality | 2026 |
| Staythorpe Farming Limited | Professional & scientific | 2018 |
| Steelwell Consultancy Limited | Hospitality | 2013 |
| Steelwell Holdings Limited | Professional & scientific | 2013 |
| Steepgrass Ltd | Information & communication | 2010 |
| Steer Tyres Limited | Wholesale & retail | 1988 |
| Steiner Gems Limited | Professional & scientific | 2026 |
| Stemgem Vases Ltd | Manufacturing | 2017 |
| Stendall Property Limited | Construction | 2019 |
| Stephanie Whitchurch Limited | Professional & scientific | 2025 |
| Sterling Edge Properties Ltd | Real estate | 2025 |
| Steve Cook Electrical Limited | Construction | 2017 |
| Steve Wade Electrical Contractors Limited | Construction | 2003 |
| Sting Cider Ltd | Manufacturing | 2016 |
| Stirling & Moore Asset Management Solutions Ltd | Real estate | 2026 |
| Stitch Express Newark Ltd | Other services | 2024 |
| Stobart Ltd | Manufacturing | 2019 |
| Stoneware Sales Ltd | Wholesale & retail | 2023 |
| Stonish Hill Wind Farm Limited | Energy | 2006 |
| STORE365 Ltd | Real estate | 2020 |
| Stork's Nest Properties Ltd | Real estate | 2021 |
| Stormsaver Limited | Water & waste | 2003 |
| Straightup Consulting Ltd | Professional & scientific | 2025 |
| Stratis Support Services Ltd | Professional & scientific | 2025 |
| Stratum Dynamics Ltd | Information & communication | 2026 |
| Stravous Ltd | Information & communication | 2023 |
| Strawson Group Limited | Financial services | 2024 |
| Strawson Limited | Agriculture & fishing | 2001 |
| Strawson Produce Ltd | Agriculture & fishing | 2019 |
| Street-Docherty Properties Limited | Real estate | 2021 |
| Streeter Developments Limited | Real estate | 2025 |
| Streetly Hall Renewables Ltd | Real estate | 2023 |
| Stridewise Support Solutions Ltd | Health & social care | 2025 |
| Stripes Retail Ltd | Wholesale & retail | 2003 |
| Stroke 2 Strength Ltd | Administrative & support | 2025 |
| Strong & Co Inc Ltd | Professional & scientific | 2012 |
| Strong & Co Real Estates Limited | Real estate | 2018 |
| STT Electrical Services Limited | Manufacturing | 2025 |
| Sttp Leisure Limited | Hospitality | 2024 |
| Stuart Favill Consultancy Limited | Professional & scientific | 2014 |
| Stubborn Dog Games Limited | Wholesale & retail | 2020 |
| Stubton Hall Limited | Hospitality | 2008 |
| Studio-G Architecture LLP | | 2007 |
| Studio-G Associates Ltd | Professional & scientific | 1998 |
| Studweldpro - U.K. Limited | Construction | 1977 |
| Sturgess Engineering Ltd | Professional & scientific | 2024 |
| SUB100 Ltd | Wholesale & retail | 2022 |
| Sublime Projects Ltd | Construction | 2018 |
| Suggy's Gym Personal Training Limited | Arts & recreation | 2023 |
| Suggys Champions Academy C.I.C. | Education | 2026 |
| Sukh FRY Ltd | Hospitality | 2026 |
| Sumag Ltd | Manufacturing | 2014 |
| Summers Lodge Management Company Limited | Households | 2001 |
| Sun-Rise Systems 2000 Limited | Manufacturing | 1999 |
| Sundae Body Ltd | Wholesale & retail | 2020 |
| Sundial Partners Limited | Professional & scientific | 2024 |
| Sunflower Eco Ltd | Wholesale & retail | 2026 |
| Sunnyside Day Nursery and Play Centre Limited | Education | 2014 |
| Sunnyside Play Centre Ltd | Arts & recreation | 2019 |
| Sunnyside UP Farm Shop Ltd | Wholesale & retail | 2018 |
| Sunrise & Sand Dunes Ltd | Hospitality | 2026 |
| Sunrise East Limited | Agriculture & fishing | 2004 |
| Sunrise Window Systems Limited | Manufacturing | 2001 |
| Superglide Aluminium Ltd | Manufacturing | 2023 |
| Supersalon Group Ltd | Other services | 2025 |
| Superstar Speakers Events Limited | Professional & scientific | 2017 |
| Superstar Speakers Memorabilia Limited | Wholesale & retail | 2019 |
| Support and Friendship Limited | Health & social care | 2016 |
| Supported Homes Limited | Administrative & support | 2006 |
| Supporting Giving Ltd | Professional & scientific | 2014 |
| Surex IE Ltd | Financial services | 2022 |
| Surveillance Electronics Limited | Manufacturing | 1967 |
| Sustain International Ltd | Professional & scientific | 2022 |
| Sustainable Building Technologies Ltd | Wholesale & retail | 2010 |
| Sustainable Solutions Ltd | Professional & scientific | 2020 |
| SW Flue Installations Ltd | Construction | 2021 |
| Swain Court Management Company Limited | Real estate | 2006 |
| Swallow Engineering Services LLP | | 2022 |
| Swallow Plant and Haulage Limited | Transport & logistics | 2024 |
| Swan & Salmon Ltd | Hospitality | 2026 |
| Swanston Harcourt Holdings Limited | Financial services | 2021 |
| Swedengate Limited | Professional & scientific | 2016 |
| Sweet Essence Media Ltd | Information & communication | 2016 |
| Sweetiz Ltd | Wholesale & retail | 2021 |
| Swift Accountancy and Finance Ltd | Professional & scientific | 2023 |
| Swift Accounting Solutions Ltd | Professional & scientific | 2003 |
| Swing Hand Car Wash Limited | Wholesale & retail | 2025 |
| Swole Studios Ltd | Information & communication | 2024 |
| Swxrd Homes Limited | Real estate | 2024 |
| Sycamore Dining CIC | Hospitality | 2018 |
| Sycamore Solutions and Services Ltd | Transport & logistics | 2021 |
| Sydney Brown Construction Limited | Construction | 2003 |
| Sydney Brown Developments Limited | Construction | 2022 |
| Syerston Hall Park Management Company Limited | Households | 1989 |
| Synexus Financial Limited | Professional & scientific | 2017 |
| Syscat Limited | Information & communication | 2002 |
| T & T Ltd | Wholesale & retail | 2017 |
| T J H Accounts Limited | Professional & scientific | 2007 |