| Space Between Group Limited | Professional & scientific | 2006 |
| Spacemaker Architects LLP | | 2021 |
| Spainwilliams Limited | Professional & scientific | 2007 |
| Spanish Star Ltd | Administrative & support | 2025 |
| Spark 9 LLP | | 2013 |
| Sparkers Electrical Ltd | Construction | 2024 |
| Sparkle TV Ltd | Information & communication | 2008 |
| Sparktacular Limited | Construction | 2018 |
| Sparrow Oast Dressage Ltd | Extraterritorial | 2023 |
| Spartan Drainage Ltd | Water & waste | 2025 |
| Spartan Drilling Services Ltd | Construction | 2020 |
| Spartan Servicing Ltd | Professional & scientific | 2025 |
| Sparxgroup Limited | Construction | 2018 |
| SPD Electrical Contractors Limited | Construction | 2010 |
| Spec Motorsport Ltd | Wholesale & retail | 2018 |
| Spec Power Ltd | Professional & scientific | 2024 |
| Specialised Engineering Solutions (UK) Limited | Professional & scientific | 2020 |
| Specialist Airport Services Limited | Other services | 1987 |
| Specialist Healthcare Consulting (UK) Limited | Professional & scientific | 2025 |
| Specsure Consultancy Limited | Professional & scientific | 2025 |
| Spectest UK Ltd | Professional & scientific | 2021 |
| Spectrum MVE Ltd | Professional & scientific | 2012 |
| SPECTRUM7 Ltd | Professional & scientific | 2025 |
| Speed 9495 Limited | Extraterritorial | 1965 |
| Speed 9763 Limited | Administrative & support | 2003 |
| Speed Automotives Kent Ltd | Wholesale & retail | 2025 |
| Speed Autos Kent Ltd | Wholesale & retail | 2025 |
| Spellstack Limited | Information & communication | 2025 |
| Spelthorne Business Forum C.I.C. | Arts & recreation | 2018 |
| Spenkins Ltd | Professional & scientific | 2025 |
| Speranza Caffè Limited | Hospitality | 2022 |
| Sphinx Clothing Company Limited | Wholesale & retail | 2022 |
| Sphinx Companies Limited | Financial services | 2022 |
| Sphinx Distillery Limited | Wholesale & retail | 2022 |
| Sphinx Holdings Limited | Financial services | 2022 |
| Sphinx Incorporated Limited | Financial services | 2022 |
| Sphinx Lettings Limited | Households | 2022 |
| Spice Garden Ashford Limited | Hospitality | 2015 |
| Spice of India Ashford Ltd | Hospitality | 2021 |
| Spinneys Sourcing Limited | Wholesale & retail | 1986 |
| Spiral Consultants Limited | Other services | 2014 |
| Spiu Ltd | Wholesale & retail | 2026 |
| Splashbax Ltd | Professional & scientific | 2024 |
| Splendid Supported Accommodations Limited | Health & social care | 2023 |
| Splendid Supported Housing Limited | Real estate | 2019 |
| SPM Footings Limited | Construction | 2022 |
| Spooner Glass Ltd | Manufacturing | 2024 |
| Spooner Glass Properties Ltd | Real estate | 2025 |
| Sport in Care Ltd | Financial services | 2020 |
| Sporting Wines Ltd | Financial services | 2026 |
| Sports 7 Limited | Education | 2018 |
| Spotlight Acting Ltd | Education | 2022 |
| Spotpixle Studios Ltd | Information & communication | 2024 |
| Spraytacular Limited | Construction | 2023 |
| Spred Ltd | Manufacturing | 2024 |
| Sprider UK Limited | Administrative & support | 2021 |
| Spring Grove Oast Residents Association Limited | Real estate | 1994 |
| Spring Grove School 2003 | Education | 2003 |
| Spring High Ltd | Information & communication | 2021 |
| Springs Healthcare Limited | Wholesale & retail | 2017 |
| Sprinks Folkestone Ltd | Financial services | 2007 |
| Sprint Data Systems Ltd | Information & communication | 1992 |
| Sprint Verse Limited | Information & communication | 2026 |
| Sprofessionals Limited | Wholesale & retail | 2023 |
| SPS Safety Limited | Construction | 2007 |
| Spun Ltd | Information & communication | 2014 |
| Spurling Cannon Secretaries Limited | Administrative & support | 2024 |
| Spyder Rigging Ltd | Construction | 2021 |
| SQ Property and Investments Limited | Real estate | 2021 |
| SQA Mentoring Ltd | Information & communication | 2024 |
| Sqlsc Limited | Information & communication | 2012 |
| Square Gain Limited | Professional & scientific | 2015 |
| Square Stone Media Ltd | Information & communication | 2023 |
| Squeaknclean Ltd | Administrative & support | 2025 |
| Squid Consultants Limited | Information & communication | 2008 |
| Squid Solar Limited | Construction | 2025 |
| Squids Gate Farm Ltd | Agriculture & fishing | 2025 |
| Squiggle Consult Ltd | Professional & scientific | 2017 |
| Squiggle Probate Limited | Professional & scientific | 2021 |
| SR-2 Construction Ltd | Construction | 2016 |
| Srcsdb Limited | Construction | 2016 |
| SRD Group Limited | Arts & recreation | 2001 |
| Sreehith Limited | Information & communication | 2017 |
| SRG Surveying Ltd | Construction | 2008 |
| SRI Ganesh Ltd | Health & social care | 2016 |
| SRI Mahathi Limited | Other services | 2012 |
| Sriven Consultancy Limited | Information & communication | 2016 |
| SRK Testing Ltd | Professional & scientific | 2018 |
| SS Consultation Ltd | Professional & scientific | 2024 |
| SS Design Studio Limited | Professional & scientific | 2024 |
| SS UK Medical Services Ltd | Administrative & support | 2022 |
| Ssdd Performace Limited | Other services | 2017 |
| Ssdevelopmentspvt Ltd | Real estate | 2025 |
| SSJ Residential Limited Liability Partnership | | 2021 |
| SSK Food & Wine Ltd | Wholesale & retail | 2016 |
| Sslans Ltd | Health & social care | 2025 |
| SSM Healthcare Ltd | Health & social care | 2022 |
| SSP Maintenance Ltd | Administrative & support | 2019 |
| Sspd Consulting Limited | Professional & scientific | 2025 |
| SSR and Sons Land Ltd | Construction | 2023 |