| Slipstream Engineering Ltd | Professional & scientific | 2017 |
| SLK Scaffolding Ltd | Construction | 2017 |
| Slkx Limited | Professional & scientific | 2019 |
| SLM Accounting Services Ltd | Professional & scientific | 2025 |
| SLM Haulage Ltd | Transport & logistics | 2020 |
| SLN EN V Ltd | Hospitality | 2021 |
| Slow Creature Ltd | Manufacturing | 2025 |
| Slow Rise Bakery Ltd | Manufacturing | 2019 |
| Slowrush Limited | Information & communication | 2024 |
| SLP Performance College Ltd | Education | 2022 |
| SLT Drop Ltd | Administrative & support | 2026 |
| Slug Speed Engineering Ltd | Manufacturing | 2017 |
| Slung LOW Limited | Arts & recreation | 2011 |
| Sluv Labels Ltd | Wholesale & retail | 2025 |
| SLW Advisory Ltd | Professional & scientific | 2025 |
| SLW Group Ltd | Information & communication | 2026 |
| SM ALI Properties Ltd | Real estate | 2021 |
| SM Capital Management Ltd | Professional & scientific | 2026 |
| SM Consultancy Services Ltd | Professional & scientific | 2022 |
| SM Investment Holdings Limited | Real estate | 2024 |
| SM Marketing Group Limited | Professional & scientific | 2025 |
| SM MOT Luton Ltd | Wholesale & retail | 2025 |
| SM Motor Group Limited | Wholesale & retail | 2025 |
| SM Properties and Investments Ltd | Real estate | 2022 |
| Sm-Km Express Logistics Limited | Transport & logistics | 2023 |
| SM103 | Financial services | 2009 |
| SM104 | Financial services | 2009 |
| SM105 | Financial services | 2009 |
| SM106 | Professional & scientific | 2009 |
| SM107 | Financial services | 2009 |
| SM7 Ventures Limited | Professional & scientific | 2014 |
| Sm@Rtbars Ltd | Information & communication | 2019 |
| SMA Grill'O Leeds Ltd | Hospitality | 2020 |
| SMA Optical Ltd | Health & social care | 2022 |
| Small Business Accountants Leeds Ltd | Professional & scientific | 2019 |
| Small Business Accounting SBA Limited | Professional & scientific | 2017 |
| Smallkind Limited | Wholesale & retail | 2019 |
| Smalltalk Studio Limited | Information & communication | 2019 |
| Smalltree Limited | Professional & scientific | 2022 |
| Smann Trading Limited | Other services | 2001 |
| Smann Wholesalers Limited | Other services | 2005 |
| Smart & Shiny | | 1995 |
| Smart 360 Services Ltd | Administrative & support | 2016 |
| Smart ADD Media Limited | Professional & scientific | 2018 |
| Smart AI Solutions Limited | Information & communication | 2023 |
| Smart Appliance Care Ltd | Administrative & support | 2020 |
| Smart Axis Stage Engineering Limited | Manufacturing | 2024 |
| Smart Barbers Leeds Ltd | Other services | 2026 |
| Smart Business Link Limited | Financial services | 2015 |
| Smart Business Ltd | Administrative & support | 2025 |
| Smart Cabling Ltd | Construction | 2015 |
| Smart Care Cleaning Ltd | Administrative & support | 2023 |
| Smart Care Group Limited | Health & social care | 2020 |
| Smart Care Security Group Ltd | Administrative & support | 2025 |
| Smart Care Systems U.K. Ltd | Information & communication | 2018 |
| Smart Care Vending Ltd | Hospitality | 2024 |
| Smart Choice Vehicles Ltd | Wholesale & retail | 2024 |
| Smart Clean FM Limited | Other services | 2024 |
| Smart Cleaning Expert Ltd | Administrative & support | 2025 |
| Smart Cleaning Services Limited | Manufacturing | 2026 |
| Smart Construction & Cleaning Ltd | Construction | 2022 |
| Smart Dental Ceramics Ltd | Other services | 2014 |
| Smart Digital Platform Ltd | Information & communication | 2019 |
| Smart Door Controls Ltd | Construction | 2011 |
| Smart Electrical (UK) Ltd. | Construction | 2003 |
| Smart Electricite Ltd | Construction | 2026 |
| Smart Finish Home Improvements Ltd | Construction | 2025 |
| Smart Gadget Repairs Limited | Wholesale & retail | 2025 |
| Smart Gallery Trading Limited | Wholesale & retail | 2014 |
| Smart Gardens UK Limited | Administrative & support | 2018 |
| Smart GAS Plumbing & Heating Limited | Construction | 2016 |
| Smart General Practice Ltd | Information & communication | 2025 |
| Smart Glazing Ltd | Construction | 2013 |
| Smart Global Reach Limited | Information & communication | 2017 |
| Smart Growth Consulting Ltd | Professional & scientific | 2022 |
| Smart Hand Car Wash Yorkshire Limited | Other services | 2023 |
| Smart Healthcare Compliance Ltd | Public administration | 2021 |
| Smart Homes Global Ltd | Construction | 2022 |
| Smart Homes Services Ltd | Real estate | 2024 |
| Smart Ideas UK Limited | Information & communication | 2002 |
| Smart Insights (Marketing Intelligence) Limited | Information & communication | 2010 |
| Smart Integrated Systems Limited | Construction | 2017 |
| Smart Investment and Management Limited | Real estate | 2017 |
| Smart Landscaping (Leeds) Limited | Administrative & support | 2011 |
| Smart Lett Leeds Ltd | Real estate | 2021 |
| Smart Maintenance and Logistics Recruitment Ltd. | Transport & logistics | 2020 |
| Smart MCT Limited | Professional & scientific | 2020 |
| Smart Medical Services Limited | Health & social care | 2015 |
| Smart Mobile and Computers Ltd | Wholesale & retail | 2025 |
| Smart Motors Transport Ltd | Wholesale & retail | 2026 |
| Smart Navigation Ltd | Professional & scientific | 2025 |
| Smart OHM (Leeds) Ltd | Construction | 2024 |
| Smart Organic Solutions Limited | Administrative & support | 2010 |
| Smart Properties LS8 Ltd | Real estate | 2024 |
| Smart Repair Group Holdings Ltd | Financial services | 2024 |
| Smart Residential Limited | Construction | 2006 |
| Smart SA Ltd | Real estate | 2018 |
| Smart Scooters Ltd | Wholesale & retail | 2020 |
| Smart Sense Accountants Ltd | Professional & scientific | 2021 |
| Smart Speech Therapy Ltd | Health & social care | 2022 |