| JMC Property Developers Limited | Real estate | 2021 |
| Jmce Holdings Ltd | Real estate | 2017 |
| JME Controls Limited | Construction | 2014 |
| JME Process Plant Limited | Wholesale & retail | 2020 |
| JMI Electrical Services Limited | Construction | 2017 |
| JMP Supplies Ltd | Wholesale & retail | 2024 |
| JMP Windows Limited | Manufacturing | 2003 |
| JMT Accountancy Limited | Professional & scientific | 2020 |
| JMT Print T/A Trowers Creative Ltd | Manufacturing | 2025 |
| JMW Synergy Ltd | Other services | 2025 |
| JMW Therapeutic Services Ltd | Health & social care | 2022 |
| JN Contracts Limited | Extraterritorial | 2012 |
| JN Solutions Staffordshire Limited | Real estate | 2011 |
| JNM Coins Ltd | Wholesale & retail | 2020 |
| Jnmd Limited | Construction | 2006 |
| JNR Motorcycles Ltd. | Administrative & support | 2020 |
| JO Barker Limited | Administrative & support | 2009 |
| JO Johnson Family Law Limited | Professional & scientific | 2015 |
| Jo'Tent Integrated Service Limited | Health & social care | 2025 |
| Joad Company Ltd | Wholesale & retail | 2019 |
| Joan Lockyer Consulting Ltd | Education | 2024 |
| JOB HQ Ltd | Administrative & support | 2019 |
| JOE Mcclurg Registered Farrier Ltd | Agriculture & fishing | 2025 |
| JOE Taft Groundworks Limited | Construction | 2019 |
| JOE.M1992 Limited | Professional & scientific | 2013 |
| Joel Milton Willis Limited | Other services | 2009 |
| John Brooks Property Services Limited | Construction | 2026 |
| John Copeland Consulting Limited | Professional & scientific | 2018 |
| John Daniels Builders Limited | Construction | 2012 |
| John Dulson Diesel Services Ltd | Wholesale & retail | 2009 |
| John Hawkins Transport Limited | Transport & logistics | 2013 |
| John Haydon & Sons (Biddulph) Limited | Transport & logistics | 1948 |
| John L. Smith Autos. Limited | Wholesale & retail | 1976 |
| John Love Estates Limited | Real estate | 2019 |
| John Mackay Consulting Limited | Information & communication | 2024 |
| John Rice Motors Limited | Wholesale & retail | 2003 |
| John Street Stores Limited | Wholesale & retail | 2024 |
| John Trigg Holdings Limited | Manufacturing | 2023 |
| Johnel Ltd | Transport & logistics | 2022 |
| Johnny M Ltd | Transport & logistics | 2022 |
| Johnny's Autos Ltd | Wholesale & retail | 2023 |
| Johnson & Cawley Limited | Construction | 1974 |
| Johnson Estate Developments Ltd | Real estate | 2024 |
| Johnson Health Tech UK Limited | Wholesale & retail | 2007 |
| Johnson Progress (2012) Limited | Manufacturing | 2012 |
| Johnson Progress Limited | Professional & scientific | 2008 |
| Johnson's Building Holding Ltd | Real estate | 2026 |
| Johnson's Day Nursery Ltd | Education | 2015 |
| Johnsons Autos Normacot Ltd | Wholesale & retail | 2024 |
| Johnson’S Autos Fenton Ltd | Wholesale & retail | 2023 |
| Johnson’S Barbershop Ltd | Other services | 2024 |
| Johnston Coaches Ltd | Transport & logistics | 2013 |
| Join the Dots Impact Holdings Limited | Administrative & support | 2025 |
| Join the Dots Impact Ventures Limited | Administrative & support | 2025 |
| Joinali Bedrooms and Kitchens Limited | Manufacturing | 2025 |
| Joja Home Ltd | Wholesale & retail | 2020 |
| Jojo Housing Limited | Real estate | 2015 |
| Joken CIC | Health & social care | 2024 |
| Jokera Holding's Ltd | Administrative & support | 2026 |
| Jomax Controls Ltd | Wholesale & retail | 2021 |
| Jomax Developments Ltd | Construction | 2020 |
| Jomay Limited | Wholesale & retail | 2025 |
| JON Beech Recovery Limited | Wholesale & retail | 1995 |
| JON Brown Hospitality Consulting Ltd | Professional & scientific | 2024 |
| JON Hewitt Bespoke Ltd | Manufacturing | 2026 |
| Jonathan Gullis Ltd | Information & communication | 2024 |
| Jonathan Harter Limited | | 1969 |
| Jones & Shuffs (Heavyside) Limited | Wholesale & retail | 1954 |
| Jones & Shuffs (KM) Limited | Wholesale & retail | 1995 |
| Jones Mason Properties Limited | Professional & scientific | 2009 |
| Jones Property Sourcing Limited | Real estate | 2025 |
| Jonkas Finance Limited | Real estate | 2024 |
| Jonkas Holdings Limited | Financial services | 2024 |
| Jonkas Real Estate 1 Limited | Real estate | 2024 |
| Jonkas Real Estate 2 Limited | Real estate | 2024 |
| Jonny Sals Home Improvements Limited | Wholesale & retail | 2025 |
| Jood's Chicken 2 Go Limited | Hospitality | 2018 |
| Joojz Medical Ltd | Health & social care | 2024 |
| Jordan Accountants Limited | Professional & scientific | 2020 |
| Jordan Robinson Limited | Administrative & support | 2024 |
| JOS Travel Ltd | Administrative & support | 2013 |
| Josabbs Limited | Health & social care | 2023 |
| Josefata Ltd | Construction | 2019 |
| Joseph Dixon Psychology Ltd | Health & social care | 2019 |
| Joseph Jones(Newcastle,Staffs)Limited | Real estate | 1933 |
| Journeyology Limited | Professional & scientific | 2023 |
| Joy Macesons Ltd | Construction | 2020 |
| Joy Muramba Health Care Limited | Health & social care | 2025 |
| Joyn 100 DS Ltd | Construction | 2022 |
| Joyn Consulting Limited | Real estate | 2013 |
| Joyn Holdings Limited | Real estate | 2017 |
| Joyn Investments Ltd | Real estate | 2021 |
| Joyn Property Limited | Real estate | 2014 |
| Joyn S.A. Ltd | Real estate | 2022 |
| Joysi Care Ltd | Health & social care | 2025 |
| Jozef P & SON Transport UK Ltd | Transport & logistics | 2018 |
| JP Barrow Properties Limited | Hospitality | 2020 |
| JP Building & Joinery Limited | Construction | 2020 |
| JP Filtration Limited | Professional & scientific | 2008 |
| JP Web Solutions Limited | Information & communication | 2011 |