| Spec Car Dealership Ltd | Wholesale & retail | 2018 |
| Special New Fruit Licensing Limited | Professional & scientific | 2004 |
| Special Operations Limited | Manufacturing | 2017 |
| Specialist Activity Camps Limited | Education | 2026 |
| Specialist Automotive Services Ltd | Wholesale & retail | 2015 |
| Specialist Car Services Ltd | Wholesale & retail | 2025 |
| Specialist Floorworx Ltd | Construction | 2023 |
| Specialist Health Solutions Holdings Limited | Professional & scientific | 2022 |
| Specialist Health Solutions Limited | Other services | 2014 |
| Specialist Painting Group Limited | Professional & scientific | 2012 |
| Specialist Sealing Products Limited | Administrative & support | 2015 |
| Specialist Wallcoating Services Ltd | Construction | 2025 |
| Speciosa Limited | Financial services | 2019 |
| Specter Marketing Limited | Other services | 2017 |
| Spectis Aviation Ltd | Construction | 2025 |
| Spectradev Ltd | Transport & logistics | 2019 |
| Spectrum Total Engineering Limited | Information & communication | 2018 |
| Speech Connect Ltd | Health & social care | 2025 |
| Speechley Property Consultants Limited | Professional & scientific | 2016 |
| Speechley Technical Services Ltd | Professional & scientific | 2016 |
| Speed Agency Limited | Information & communication | 1983 |
| Speed Booking Consulting Limited | Information & communication | 2024 |
| Speed Booking UK Limited | Education | 2023 |
| Speed Dragon Ltd | Transport & logistics | 2025 |
| Speed Estates Limited | Real estate | 2019 |
| Speed Holdings Limited | Real estate | 2016 |
| Speed Tests UK Limited | Education | 2025 |
| Speed Vape Limited | Wholesale & retail | 2023 |
| Speedway Alves Ltd | Transport & logistics | 2019 |
| Speedy Donkey Limited | Transport & logistics | 2025 |
| Speedy Logistic Peterborough Ltd | Construction | 2023 |
| Spellcrow Ltd | Wholesale & retail | 2017 |
| Spencer FOX Relocation Limited | Administrative & support | 2007 |
| SPG Home Improvement Ltd | Construction | 2024 |
| Sphinxer Ltd | Wholesale & retail | 2020 |
| Spice Twenty 3 Ltd | Hospitality | 2025 |
| Spices World Limited | Wholesale & retail | 2018 |
| Spider Car Services Ltd | Other services | 2015 |
| Spider Tires Ltd | Wholesale & retail | 2025 |
| Spierings Mobile Cranes Ltd | Manufacturing | 2019 |
| Spin Rider Ltd | Information & communication | 2025 |
| Spina Bifida, Hydrocephalus, Information, Networking, Equality - Shine | Health & social care | 1966 |
| Spinifex Holidays Ltd | Hospitality | 2020 |
| Spinney House Management Company Ltd | Households | 2011 |
| Spinroom Studios Ltd | Arts & recreation | 2020 |
| Spiral Gymnastics Limited | Arts & recreation | 2011 |
| Spiral-X Limited | Information & communication | 2004 |
| Spire Properties (Deeping) Ltd | Construction | 2024 |
| Spire View, Whittlesey Management Company Ltd | Households | 2019 |
| Spirelabs Ltd | Information & communication | 2025 |
| Spirgys Limited | Construction | 2026 |
| Spirit and Rose Ltd | Wholesale & retail | 2026 |
| Spirit Milk Ltd | Wholesale & retail | 2026 |
| Spiriteddawn Limited | Other services | 2023 |
| Spitfly Construction Ltd | Construction | 2016 |
| SPK Healthcare Ltd | Health & social care | 2010 |
| SPO Property Investments Ltd | Real estate | 2020 |
| Spoadco Limited | Professional & scientific | 2022 |
| Sportfolio Images Limited | Professional & scientific | 2008 |
| Sports Drop Ltd | Wholesale & retail | 2023 |
| Sports Surface Maintenance Ltd | Construction | 2010 |
| SPORTSCARDSUK00 Ltd | Wholesale & retail | 2023 |
| Spot Cash Limited | Financial services | 1989 |
| Spotless Clean Limited | Administrative & support | 2015 |
| Spotless Sparkles Ltd | Administrative & support | 2025 |
| Spotlex Cleaning Company Ltd | Administrative & support | 2023 |
| SPR Star Ltd | Hospitality | 2024 |
| SPRAJ11 Limited | Real estate | 2020 |
| Spreading the Gospel Video Services Ltd | Information & communication | 2014 |
| Spriggs Reclaim Limited | Water & waste | 2023 |
| Spring Property Relocation Ltd | Hospitality | 2024 |
| Spring Street Developments Ltd | Construction | 2014 |
| SPRING2HEALTH Ltd | Health & social care | 2018 |
| Springboard Property Ltd | Construction | 2013 |
| Springemerge Consulting Ltd | Professional & scientific | 2022 |
| Springfield 2025 Limited | Households | 2025 |
| Springfields Motors Ltd | Wholesale & retail | 2023 |
| Sprints Ahead Ltd | Information & communication | 2025 |
| Sprk Media Ltd | Professional & scientific | 2025 |
| SPS LMD Limited | Administrative & support | 2013 |
| SPS59 Ltd | Wholesale & retail | 2011 |
| Spudway Limited | Hospitality | 2018 |
| SPX Logistics Ltd | Transport & logistics | 2026 |
| Spydercars Ltd | Wholesale & retail | 2009 |
| Spydy Transport Ltd | Transport & logistics | 2021 |
| SQ Haus Limited | Hospitality | 2019 |
| SQ Plus Limited | Wholesale & retail | 2016 |
| SQR Pizza Ltd | Hospitality | 2026 |
| Square Ashlar Properties Limited | Real estate | 2016 |
| Square Corporation Ltd | Wholesale & retail | 2018 |
| SQUARE4 Limited | Administrative & support | 2024 |
| SQUARED4 Ltd | Information & communication | 2019 |
| Squashed Activewear Ltd | Wholesale & retail | 2025 |
| Squeegee Ltd | Administrative & support | 2022 |
| Squirrel Café Limited | Hospitality | 2026 |
| SR Electrical & Renewables Ltd | Construction | 2026 |
| SR OIL Speciality Ltd | Wholesale & retail | 2022 |
| SR Star Ltd | Hospitality | 2022 |
| SR67 Limited | Real estate | 2022 |
| SRA Alizada Properties Ltd | Real estate | 2023 |