| Spandrel Ltd | Professional & scientific | 2024 |
| Spantec Services Ltd | Wholesale & retail | 2022 |
| Sparkles PAW Paradise Limited | Agriculture & fishing | 2025 |
| Sparkling Minds Day Nursery Ltd | Health & social care | 2022 |
| Sparkling Oven Solutions Limited | Administrative & support | 2025 |
| Sparksai Consulting Limited | Professional & scientific | 2024 |
| Sparrow Electrical and Maintenance Ltd | Construction | 2021 |
| Sparrowhawk Management Services Ltd | Administrative & support | 2015 |
| Sparrowhawk Risk Advisory Limited | Professional & scientific | 2026 |
| Sparrows Farm Estates Limited | Professional & scientific | 2019 |
| SPC Solutions Limited | Administrative & support | 2009 |
| Spearpoint and SON Ltd | Water & waste | 2021 |
| Spebec Properties Limited | Construction | 1954 |
| Special Touches Ltd | Wholesale & retail | 2015 |
| Specialised Diving Services Ltd | Extraterritorial | 2017 |
| Specialised Surveying Limited | Construction | 2015 |
| Specialist Access Solutions Ltd | Administrative & support | 2023 |
| Specialist Bathrooms & Property Services Limited | Construction | 2016 |
| Specialist Environmental Services Limited | Construction | 1977 |
| Specialist Firearms Limited | Wholesale & retail | 2018 |
| Specialist Medical Ltd | Health & social care | 2025 |
| Specialist Site Management Limited | Administrative & support | 2015 |
| Spencer Fellows & Co Limited | Professional & scientific | 2011 |
| Spencer Sellers Management Ltd | Real estate | 2018 |
| Spencer West Global Limited | Administrative & support | 2020 |
| SPF Professional Services Ltd | Professional & scientific | 2018 |
| SPG Pharma Limited | Wholesale & retail | 2018 |
| Sphereview Medicare Limited | Health & social care | 2025 |
| Sphereweb Consulting Limited | Construction | 2008 |
| Spice Lounge Chelmsford Ltd | Hospitality | 2022 |
| Spider Tower Crane Services Limited | Manufacturing | 2019 |
| Spike (Essex) Limited | Construction | 1996 |
| Spindles Carpentry & Building Services Ltd | Construction | 2025 |
| Spinesavers Limited | Wholesale & retail | 2011 |
| Spinnaker IM NO. 2 Ltd | Financial services | 2014 |
| Spiral Assets Ltd | Wholesale & retail | 2018 |
| Spires UK Holdings Ltd | Financial services | 2021 |
| Spirit Semiconductor Limited | Professional & scientific | 2020 |
| Spirits Bar & Games Ltd | Hospitality | 2023 |
| Spiritual Services Ltd | Other services | 2023 |
| SPK HME Ltd | Real estate | 2020 |
| Splendid Engineering Ltd | Professional & scientific | 2021 |
| SPM Local Ltd | Wholesale & retail | 2024 |
| SPM Renovations Ltd | Real estate | 2025 |
| SPM Rentals Ltd | Real estate | 2025 |
| SPO Consultants Limited | Professional & scientific | 2013 |
| Spoonbill Data Limited | | 1987 |
| Sport 4 Business Limited | Arts & recreation | 2000 |
| Sport for Confidence C.I.C. | Other services | 2015 |
| Sport Speculator Ltd | Information & communication | 2021 |
| Sports & Leisure Holdings Limited | Financial services | 2020 |
| Sports Activity Company Limited | Arts & recreation | 1959 |
| Sports Engineer UK Ltd | Education | 2019 |
| Sports Lounge UK Limited | Extraterritorial | 2005 |
| Sportsman Personal Training Ltd | Education | 2023 |
| SPOT18 Ltd | Real estate | 2017 |
| Spotless H20 Limited | Water & waste | 2017 |
| Spotless Locations Limited | Administrative & support | 2001 |
| Spotless Pink Army Cleaning Ltd | Administrative & support | 2023 |
| Spotlight Multimedia Ltd | Education | 2016 |
| Spotnet Advertising Limited | Administrative & support | 2020 |
| SPR Financial Services Limited | Professional & scientific | 2026 |
| Spray Insulations Limited | Construction | 2009 |
| Spread Creative Limited | Information & communication | 2017 |
| Sprilia Ltd | Wholesale & retail | 2020 |
| Springbok Housing Ltd | Real estate | 2025 |
| Springfield Asset Management Ltd | Professional & scientific | 2011 |
| Springfield Barbers (S.A.) Limited | Other services | 2025 |
| Springfield Bees Pre-School | Education | 2010 |
| Springfield Decorating Ltd | Construction | 2024 |
| Springfield Home Support Limited | Health & social care | 2025 |
| Springfield Renovations Limited | Construction | 2014 |
| Springfield Road (Chelmsford) Residents Management Company Limited | Households | 2003 |
| Springfield Stars Ltd | Education | 2021 |
| Springfield Villa Limited | Real estate | 1979 |
| Springfields (Brightlingsea) RTM Company Limited | Real estate | 2017 |
| Springmerch Ltd | Arts & recreation | 2013 |
| Springpoint Property Investments Limited | Real estate | 2026 |
| Springs Place Limited | Real estate | 2022 |
| Sprintech Athletics Limited | Arts & recreation | 2020 |
| Sprinter Studios Limited | Information & communication | 2026 |
| Spritely Scaffolding Ltd | Construction | 2025 |
| Spruce Healthcare Ltd | Administrative & support | 2019 |
| Spruce Restaurant Ltd | Hospitality | 2021 |
| SPS Engineering Limited | Administrative & support | 2004 |
| Spud Station Limited | Hospitality | 2024 |
| Square Edge Solutions Ltd | Manufacturing | 2002 |
| SQUARE17 IT Solutions Ltd | Information & communication | 2017 |
| Squarestar Digital Limited | Information & communication | 2019 |
| SR Camps Ltd | Arts & recreation | 2023 |
| SR Safety Solutions Ltd | Professional & scientific | 2012 |
| SR Sports Coaching Limited | Arts & recreation | 2017 |
| SRC Security Systems Ltd | Construction | 2012 |
| Sreetechs Ltd | Information & communication | 2014 |
| Sreshtaenterprisesltd Ltd | Manufacturing | 2025 |
| SRI Kanyaka Ltd | Real estate | 2026 |
| SRI Lvkts Ltd | Health & social care | 2023 |
| SRI Matre Limited | Hospitality | 2025 |
| SRI Rudra Holdings Limited | Real estate | 2024 |
| Srineelesh Property Limited | Real estate | 2017 |