| SLA Properties & Consulting Ltd | Real estate | 2025 |
| Slater Holdings Ltd | Financial services | 2025 |
| Slay Empire Limited | Wholesale & retail | 2023 |
| Slayedbyj.A Limited | Other services | 2025 |
| Sleight Insights Limited | Professional & scientific | 2025 |
| Slfi Ltd | Health & social care | 2023 |
| Slick Logistics Ltd | Transport & logistics | 2025 |
| Slick Parts Limited | Wholesale & retail | 2004 |
| Slick Recycling Ltd | Transport & logistics | 2012 |
| Sllp Limited | Construction | 2021 |
| Sllp Rental Limited | Real estate | 2021 |
| Sloanstreet Ltd | Professional & scientific | 2013 |
| Slowline Limited | Professional & scientific | 2017 |
| SLS Premier Limited | Real estate | 2021 |
| Slump Cinema Limited | Information & communication | 2025 |
| SM & Co Consultants Ltd | Professional & scientific | 2019 |
| SM ACP Ltd | Health & social care | 2021 |
| SM Administration Services Limited | Administrative & support | 2018 |
| SM Buckley Limited | Professional & scientific | 2017 |
| SM Finance Data Ltd | Professional & scientific | 2022 |
| SM Legal Ltd | Professional & scientific | 2026 |
| SM Roofing & Building Ltd | Construction | 2025 |
| SM87 Properties Ltd | Real estate | 2024 |
| SMA Catering Ltd | Other services | 2013 |
| SMA Investments UK Ltd | Real estate | 2022 |
| SMA Private Hire Limited | Wholesale & retail | 2024 |
| Smallboy Trackbikes Cheshire Ltd | Administrative & support | 2025 |
| Smallboy Trackbikes Ltd | Administrative & support | 2016 |
| Smart Broadcast Hire Limited | Information & communication | 2022 |
| Smart Build (GM) Ltd | Construction | 2017 |
| Smart Business Review Ltd | Information & communication | 2019 |
| Smart Care Uk-Bd Ltd | Information & communication | 2025 |
| Smart Change Consultancy Ltd | Professional & scientific | 2025 |
| Smart Ecom Solutions Limited | Wholesale & retail | 2026 |
| Smart Engineering Solutions Ltd | Professional & scientific | 2023 |
| Smart Home 2025 Ltd | Real estate | 2025 |
| Smart Kids Children's Care Ltd | Education | 2007 |
| Smart Lead Ltd | Information & communication | 2019 |
| Smart Medical Solutions Ltd | Professional & scientific | 2011 |
| Smart Medicals Services Limited | Public administration | 2023 |
| Smart Mobility Network Limited | Professional & scientific | 2025 |
| Smart Occupational Health Ltd | Administrative & support | 2020 |
| Smart Phones Oldham Ltd | Wholesale & retail | 2024 |
| Smart Picks Online Ltd | Wholesale & retail | 2015 |
| Smart Plus Learning Ltd | Administrative & support | 2026 |
| Smart Refining Ltd | Water & waste | 2022 |
| Smart Revert Limited | Wholesale & retail | 2021 |
| Smart Route Motors Limited | Wholesale & retail | 2024 |
| Smart Shelving Limited | Wholesale & retail | 2024 |
| Smart Tech MCR Limited | Wholesale & retail | 2024 |
| Smart Traderz Ltd | Wholesale & retail | 2024 |
| Smart Transport Management Ltd | Professional & scientific | 2024 |
| Smart Way Hire Ltd | Administrative & support | 2018 |
| Smart+ Services Ltd | Administrative & support | 2021 |
| Smartdealz Ltd | Wholesale & retail | 2021 |
| Smartel Communications Ltd | Wholesale & retail | 2015 |
| Smarter Water Consultants Ltd | Professional & scientific | 2024 |
| Smartex Enterprises Ltd | Construction | 2023 |
| Smartguy Ecom Limited | Wholesale & retail | 2026 |
| Smartsaver Limited | Professional & scientific | 2003 |
| Smartshipper Limited | Transport & logistics | 2025 |
| Smarttechman Limited | Manufacturing | 2024 |
| Smartz Consultants Limited | Professional & scientific | 2024 |
| Smash Catering and Events Limited | Hospitality | 2025 |
| Smash'N'Dunk Ltd | Hospitality | 2026 |
| Smashofficial Limited | Hospitality | 2021 |
| Smashtime Private Limited | Hospitality | 2025 |
| Smb.Handymans Ltd | Construction | 2025 |
| SMC Installations Limited | Information & communication | 2010 |
| Smethurst Secretarial Services Limited | Professional & scientific | 2011 |
| SMF Travel Limited | Transport & logistics | 2024 |
| SMG Project Consultancy Services Ltd | Water & waste | 2021 |
| Smidam Limited | Health & social care | 2024 |
| Smile Accountants Limited | Professional & scientific | 2010 |
| Smile Bookkeeping Limited | Extraterritorial | 2012 |
| Smile FAB Limited | Health & social care | 2024 |
| Smile Property Letts Limited | Real estate | 2024 |
| Smith Developments Limited | Professional & scientific | 2003 |
| SMK Developments Limited | Other services | 1996 |
| SML Project Delivery Limited | Professional & scientific | 2015 |
| Smnj Greenwood Media Group Ltd | Wholesale & retail | 2026 |
| Smocked Limited | Wholesale & retail | 2023 |
| Smokoholic Ltd | Wholesale & retail | 2023 |
| Smooth Electrolysis Ltd | Other services | 2026 |
| Smooth Stone Driveways & Patios Ltd | Administrative & support | 2026 |
| Smra Property Ltd | Real estate | 2024 |
| SMS Campers Ltd | Wholesale & retail | 2018 |
| SMT Traders Ltd | Wholesale & retail | 2024 |
| SN Medlock Ltd | Wholesale & retail | 2014 |
| SN Property Build and Development Limited | Construction | 2020 |
| SN Property Rentals and Investments Limited | Real estate | 2020 |
| Snaith Dental Care Limited | Health & social care | 2016 |
| Snap Travelling and Traders Ltd | Administrative & support | 2025 |
| Snapdeals Realty Ltd | Real estate | 2026 |
| SNG Developments Ltd | Construction | 2023 |
| SNG Equity Partners Limited | Real estate | 2022 |
| SNG Hotel Cleator Moor Ltd | Real estate | 2019 |
| SNG Hotel Egremont Ltd | Real estate | 2018 |
| SNG Property Management Limited | Real estate | 2023 |
| SNI Optometric Services Ltd | Health & social care | 2003 |