| Smart Electrical (JK) Ltd | Construction | 2017 |
| Smart Electrical Services Leicester Limited | Construction | 2021 |
| Smart Energy & Heating Ltd | Construction | 2019 |
| Smart Energy Maintenance Ltd | Administrative & support | 2013 |
| Smart Engineering Design Ltd | Professional & scientific | 2022 |
| Smart Exteriors Ltd | Administrative & support | 2024 |
| Smart FIX & Trade Limited | Information & communication | 2019 |
| Smart FIX Automotive Ltd | Wholesale & retail | 2025 |
| Smart FIX Solutions Limited | Wholesale & retail | 2011 |
| Smart FOX (UK) Limited | Extraterritorial | 2009 |
| Smart GAS & Power Limited | Energy | 2017 |
| Smart Girl (UK) Ltd | Manufacturing | 2004 |
| Smart Girl Leic Ltd | Manufacturing | 2024 |
| Smart Holiday Bookings Limited | Real estate | 2024 |
| Smart Home TEC Ltd | Extraterritorial | 2018 |
| Smart IBS Limited | Professional & scientific | 2015 |
| Smart Insights Smart Outcomes Ltd | Information & communication | 2022 |
| Smart Investa Hub Ltd | Financial services | 2020 |
| Smart IT Services Ltd | Transport & logistics | 2023 |
| Smart Motor Solutions Ltd | Wholesale & retail | 2018 |
| Smart Motors Ltd | Wholesale & retail | 2017 |
| Smart Move (Berkshire) Limited | Professional & scientific | 2006 |
| Smart OPS Water UK Ltd | Professional & scientific | 2020 |
| Smart Painting Solutions Ltd | Construction | 2016 |
| Smart Payments Limited | Information & communication | 2011 |
| Smart People Global Limited | Information & communication | 2025 |
| Smart Plus Taxis Ltd | Transport & logistics | 2024 |
| Smart Property Performance Ltd | Construction | 2022 |
| Smart Raids Ltd | Information & communication | 2024 |
| Smart Recruitment Agency (Midlands) Ltd | Administrative & support | 2025 |
| Smart Retail Solutions Ltd | Professional & scientific | 2015 |
| Smart Scalpel UK Ltd | Information & communication | 2025 |
| Smart Scientist Ltd | Education | 2023 |
| Smart SKS Ltd | Wholesale & retail | 2015 |
| Smart Solutions Drainage Ltd | Water & waste | 2021 |
| Smart Solutions Electrical Ltd | Construction | 2021 |
| Smart Source Ltd | Manufacturing | 2023 |
| Smart Squares Ltd | Wholesale & retail | 2022 |
| Smart Statistics Limited | Information & communication | 2022 |
| Smart Strategies Limited | Professional & scientific | 2015 |
| Smart Tax and Accounting Ltd | Professional & scientific | 2019 |
| Smart Tech Arabic Ltd | Information & communication | 2022 |
| Smart Tour Limited | Information & communication | 2018 |
| Smart Transport & Logistics Ltd | Transport & logistics | 2019 |
| Smart Travel & Holidays Ltd | Administrative & support | 2022 |
| Smart-Cash Umbrella Limited | Professional & scientific | 2017 |
| SMART4PROPERTIES Ltd | Real estate | 2020 |
| Smartask-Fm Ltd | Administrative & support | 2024 |
| Smartdealing Ltd | Real estate | 2018 |
| Smartdwell Properties Ltd | Real estate | 2023 |
| Smartedge AI Ltd | Information & communication | 2006 |
| Smartedge Solutions Ltd | Information & communication | 2005 |
| Smarter Fragrances Ltd | Wholesale & retail | 2023 |
| Smarter Supplements LAB Ltd | Wholesale & retail | 2025 |
| Smartfield Limited | Professional & scientific | 1994 |
| Smartfit Interiors Ltd | Construction | 2025 |
| Smarthaul Ltd | Transport & logistics | 2026 |
| Smarthome Connect Limited | Administrative & support | 2018 |
| Smarthome Tech Limited | Construction | 2020 |
| Smarthomeuk Limited | Wholesale & retail | 2021 |
| Smarthub Properties Ltd | Real estate | 2024 |
| Smarticles Daycare Limited | Health & social care | 2020 |
| Smartness Development Ltd | Construction | 2019 |
| Smartq Solutions Ltd | Information & communication | 2024 |
| Smartshopuk Limited | Wholesale & retail | 2026 |
| Smartsoft Services Ltd | Information & communication | 2006 |
| Smartsrive Limited | Construction | 2025 |
| Smartsy Fused Glass Limited | Manufacturing | 2024 |
| Smartwave Ltd | Construction | 2016 |
| Smartwave Online Ltd | Wholesale & retail | 2017 |
| Smartwave Services Ltd | Manufacturing | 2020 |
| Smartway Investments Limited | Financial services | 2013 |
| Smartway Media Solutions Community Interest Company | Information & communication | 2019 |
| Smartway Pharma Limited | Wholesale & retail | 2012 |
| Smartway Pharmaceuticals Limited | Wholesale & retail | 2013 |
| Smartway Property Limited | Real estate | 2013 |
| Smartway PW. Holdings Limited | Professional & scientific | 2013 |
| Smartway Wholesale Ltd | Extraterritorial | 2013 |
| Smarty Sprouts Ltd | Wholesale & retail | 2025 |
| Smash and Steak Ltd | Hospitality | 2026 |
| Smash Inc Limited | Real estate | 2021 |
| Smash Investco Limited | Real estate | 2024 |
| Smash N Desserts Ltd | Hospitality | 2026 |
| Smash N Grub Ltd | Hospitality | 2024 |
| Smash Supplements Limited | Wholesale & retail | 2026 |
| Smash Ventures Limited | Other services | 2017 |
| Smashin Patties Ltd | Hospitality | 2026 |
| Smay and Shrea Verma Ltd | Health & social care | 2014 |
| SMB Access 2 Limited | Households | 2025 |
| SMB Access Limited | Households | 2024 |
| SMB Builders Ltd | Construction | 2015 |
| SMB Computing Limited | Information & communication | 2011 |
| SMB Consult Limited | Administrative & support | 2022 |
| SMB Education Services Ltd | Education | 2016 |
| SMB Trade Centre Ltd | Wholesale & retail | 2015 |
| SMC Lifts Ltd | Manufacturing | 2022 |
| SMC Sales Limited | Wholesale & retail | 2022 |
| SMD Photography Limited | Professional & scientific | 2012 |
| SMD Solutions Ltd | Information & communication | 2025 |
| SMF (UK) Limited | Manufacturing | 2001 |