| Skylark Holdings (Kent) Limited | Financial services | 2026 |
| Skyline Blues Ltd | Real estate | 2023 |
| Skyline Property Maintenance Limited | Construction | 2004 |
| Skylinedrone Ltd | Information & communication | 2025 |
| Skypainting Ltd | Construction | 2021 |
| Skyrock Accountants Ltd. | Professional & scientific | 2012 |
| Skyrosediamond Limited | Health & social care | 2022 |
| Skyward Manpower Resource and Management Ltd | Administrative & support | 2024 |
| SL Business Consulting Ltd | Professional & scientific | 2025 |
| Slater & Spiers Limited | Construction | 2019 |
| Slav Logistics Ltd | Transport & logistics | 2024 |
| SLB Group Limited | Administrative & support | 2016 |
| Sleeptight Property Services Limited | Real estate | 2023 |
| Sluxe Property Limited | Real estate | 2013 |
| SM General Maintenance Ltd | Administrative & support | 2025 |
| Small BIZ Social Ltd | Information & communication | 2021 |
| Small Luxury Hotels Limited | Construction | 2018 |
| Small World Travel Limited | Administrative & support | 1986 |
| Smallworld Consultants Limited | Professional & scientific | 1986 |
| Smart AU Pairs & Nannies Limited | Other services | 2005 |
| Smart Barber Maidstone Limited | Other services | 2022 |
| Smart Care Imaging Limited | Health & social care | 2023 |
| Smart College Student Ltd | Administrative & support | 2024 |
| Smart Digits Ltd | Professional & scientific | 2021 |
| Smart Drylining Project Limited | Construction | 2020 |
| Smart FIX Auto’S Limited | Wholesale & retail | 2024 |
| Smart Green Energy Limited | Construction | 2020 |
| Smart Mechanical Ltd | Construction | 2020 |
| Smart Property Kent Ltd | Real estate | 2024 |
| Smart School of London Ltd | Transport & logistics | 2021 |
| Smart South East Ltd | Wholesale & retail | 2024 |
| Smart Spray Paint Ltd | Wholesale & retail | 2015 |
| Smart Taurus Ltd | Transport & logistics | 2024 |
| Smart Time Security Services Limited | Administrative & support | 2026 |
| Smart Times Security Services Ltd | Financial services | 2025 |
| Smart Upgrades Ltd | Construction | 2025 |
| Smartbi Tech Ltd | Information & communication | 2019 |
| Smartcap Innovations Ltd | Professional & scientific | 2020 |
| Smartchimp Business Specialist Ltd. | Professional & scientific | 2017 |
| Smartchimp Holdings Ltd | Financial services | 2023 |
| Smartgroup AI Limited | Information & communication | 2025 |
| Smarthome Epc's Ltd | Professional & scientific | 2025 |
| Smartline Homes Ltd | Construction | 2025 |
| SMB Graphic Solutions Ltd | Other services | 2021 |
| SMB Property Solutions Ltd | Manufacturing | 2025 |
| SME Sign Solutions Limited | Manufacturing | 2015 |
| Smed Heating Ltd | Construction | 2020 |
| Smilingsmarts Ltd | Wholesale & retail | 2025 |
| Smit Advisory Limited | Professional & scientific | 2023 |
| Smit&Enterprise Limited | Hospitality | 2024 |
| Smith - the Creative Foundry Ltd | Professional & scientific | 2017 |
| Smith Mccormick | | 1986 |
| Smiths Brothers Ltd | Transport & logistics | 2021 |
| Smithy Signalling Ltd | Professional & scientific | 2024 |
| Smitsocial.Media Limited | Information & communication | 2016 |
| SML Building Services Ltd | Construction | 2026 |
| Smlm Limited | Transport & logistics | 2020 |
| Smoke and Ventilation Engineering Ltd | Manufacturing | 2017 |
| Smoked Truffle Ltd | Hospitality | 2026 |
| Smooth Finish Construction Ltd | Construction | 2007 |
| SMS Euro Logistics Ltd | Transport & logistics | 2019 |
| Smth Services Limited | Professional & scientific | 2022 |
| Snackhub Vending Services Ltd | Wholesale & retail | 2025 |
| Snakpak Limited | Hospitality | 2025 |
| Snapwire Limited | Information & communication | 2010 |
| SNC Delivery Limited | Transport & logistics | 2018 |
| Sneakypeak Photo Limited | Professional & scientific | 2024 |
| SNO Investments Limited | Professional & scientific | 1999 |
| SNO Lines Limited | Professional & scientific | 1979 |
| Snoozewort Ltd | Arts & recreation | 2021 |
| Snow Software Limited | Information & communication | 2007 |
| SNS 77 Ltd | Construction | 2015 |
| SNS Group LLP | | 2015 |
| Snugtrove Co Ltd | Wholesale & retail | 2025 |
| SO Easy Group Limited | Financial services | 2013 |
| SO Hairdressing Limited | Administrative & support | 2007 |
| SO Medical Accounting Ltd | Professional & scientific | 2020 |
| Soak Coffee Ltd | Manufacturing | 2021 |
| Soba Circus Ltd | Other services | 2023 |
| Sobia Khan Consultancy Services Ltd | Health & social care | 2024 |
| Sobia Khan Real Estate Services Ltd | Real estate | 2024 |
| Sobody (UK) Limited | Wholesale & retail | 2021 |
| Sobriety's FOE Ltd | Hospitality | 2013 |
| Social Media Platform 1 Limited | Other services | 2016 |
| Social Power Digital Ltd | Professional & scientific | 2026 |
| Social Work Hearts Limited | Health & social care | 2024 |
| Socialroach Limited | Manufacturing | 2025 |
| Socium Consultants Ltd | Professional & scientific | 2017 |
| Sofa Point UK Ltd | Manufacturing | 2021 |
| Sofia Magic Ltd | Wholesale & retail | 2024 |
| Soficar Transport Ltd | Transport & logistics | 2024 |
| Sofimore Ltd | Health & social care | 2024 |
| Soft Incorporation Limited | Information & communication | 2026 |
| Softech Global Solutions Ltd | Information & communication | 2011 |
| Softinov Ltd | Information & communication | 2014 |
| Softinov Properties Ltd | Real estate | 2023 |
| Sogo Investments Limited | Real estate | 2021 |
| Soho Media Group Limited | Professional & scientific | 2019 |
| Soimu Trans Ltd | Construction | 2023 |
| Sojisoft Limited | Information & communication | 2024 |