| JOG Racing & Coaching Ltd | Arts & recreation | 2025 |
| Joggy's Beauty Academy Limited | Other services | 2011 |
| Jogo Behaviour Support Ltd | Education | 2012 |
| JOH4L Investment Ltd | Real estate | 2024 |
| Johan Textile Ltd | Other services | 2014 |
| John Aveyard Limited | Professional & scientific | 2016 |
| John Baker Music Limited | Information & communication | 2009 |
| John Bowen-Jones Limited | Real estate | 1976 |
| John Clifton & SON Limited | Manufacturing | 1998 |
| John Dawson Electrical Limited | Construction | 2012 |
| John Deery Interiors Limited | Construction | 2016 |
| John Fixing Ltd | Transport & logistics | 2023 |
| John Hayles Consulting Ltd | Professional & scientific | 2011 |
| John Henry Hitchin Limited | Professional & scientific | 1988 |
| John Henry Sports Limited | Wholesale & retail | 2002 |
| John Innes-Gilkes Limited | Other services | 1964 |
| John R Gammidge & Company Limited | Administrative & support | 1938 |
| John White Funeral Directors Limited | Extraterritorial | 2012 |
| John's Perfect Homes Limited | Construction | 2013 |
| Johnclad Limited | Construction | 2020 |
| Johnlux Limited | Transport & logistics | 2019 |
| Johnny Home Refurbishment Ltd | Construction | 2026 |
| Johnson Carpentry Services Ltd | Manufacturing | 2024 |
| Johnsons Installations Ltd | Construction | 2021 |
| Johnsons Plumbing and Heating Ltd | Construction | 2020 |
| Johns’ Training Ltd | Wholesale & retail | 2023 |
| Johny PAI Ltd | Construction | 2015 |
| Johnyy. Ltd | Transport & logistics | 2014 |
| Johserian L$I Ltd. | Real estate | 2021 |
| Join Consulting Limited | Professional & scientific | 2022 |
| Jointwright Limited | Real estate | 1981 |
| JOJ Venture Ltd | Transport & logistics | 2023 |
| Jojael Ltd | Wholesale & retail | 2025 |
| Jojo Pablo Limited | Construction | 2017 |
| Jokr Limited | Wholesale & retail | 2023 |
| Jolad Limited | Wholesale & retail | 2021 |
| Joli Services Limited | Professional & scientific | 2024 |
| Jollof and Tingz Ltd | Wholesale & retail | 2026 |
| Jomak Solutions Ltd | Administrative & support | 2019 |
| Jomi Property Ltd | Real estate | 2025 |
| Jomidar Lounge Ltd | Hospitality | 2022 |
| JON and Co Ltd | Real estate | 2023 |
| JON Hillyard Consulting Ltd | Professional & scientific | 2021 |
| JON Hillyard Training Ltd | Education | 2021 |
| Jonathan Brutnall & Co. Ltd | Construction | 2002 |
| Jonathan Clissold Limited | Manufacturing | 2010 |
| Jonathan Dawes Ltd | Real estate | 2021 |
| Jonathan Harris Photography Limited | Professional & scientific | 2004 |
| Jonathan Synergy Ltd | Transport & logistics | 2020 |
| Jondel Race Engines Ltd | Professional & scientific | 2024 |
| Jones Rental Investments Ltd | Real estate | 2026 |
| Jones the Furnishers Limited | Wholesale & retail | 1996 |
| Jones Tiling and Decorating Ltd | Construction | 2022 |
| Jones Transport Ltd | Transport & logistics | 2024 |
| Jonifelli Ltd | Health & social care | 2017 |
| Jonionut Ltd | Transport & logistics | 2021 |
| Jonnic Limited | Hospitality | 2011 |
| Joosh Consulting Limited | Information & communication | 2007 |
| Jordache Trans Ltd | Transport & logistics | 2023 |
| Jordan Grant Limited | Wholesale & retail | 2025 |
| Jordan Racing Team Ltd | Arts & recreation | 2014 |
| Josan Brickwork Ltd | Construction | 2024 |
| Josco Maintenance Ltd | Construction | 2026 |
| Josco Transport Ltd | Transport & logistics | 2025 |
| Joseph Barron Holdings Ltd | Financial services | 2025 |
| Joseph Monaghan Consultancy Ltd | Professional & scientific | 2024 |
| Joseph Peters Ltd. | Manufacturing | 2014 |
| Joseph-Blake HR Limited | Administrative & support | 2025 |
| Joshua J. M. Smith Ltd. | Professional & scientific | 2023 |
| Joshumba Ltd | Real estate | 2025 |
| Joss Faulkner Consultancy Ltd | Professional & scientific | 2022 |
| JOT Investments Ltd | Financial services | 2017 |
| Joublin Limited | Information & communication | 2012 |
| Jovaris Group Ltd | Financial services | 2026 |
| Jovita Consulting Limited | Health & social care | 2018 |
| Jovita Ltd | Transport & logistics | 2015 |
| Joy 2 Care Services (PVT) Limited | Health & social care | 2019 |
| Joy's Care Ltd. | Administrative & support | 2015 |
| Joyadeoana Healthcare Ltd | Health & social care | 2019 |
| Joyfell Ltd | Hospitality | 2025 |
| Joymonger UK Limited | Wholesale & retail | 2026 |
| Joynic Ltd | Health & social care | 2023 |
| JP Chapman Services Ltd | Construction | 2021 |
| JP Drylining Limited | Construction | 2004 |
| JP Estate Planning Ltd | Professional & scientific | 2015 |
| JP Plumbing & Drainage Ltd | Construction | 2011 |
| JP Primary Care Consulting Ltd | Other services | 2024 |
| JP Site Engineering Ltd | Construction | 2019 |
| JPB Building Ltd | Construction | 2025 |
| JPC Transport Services Limited | Transport & logistics | 2014 |
| JPE Ltd | Professional & scientific | 2021 |
| Jpeak Properties Ltd | Real estate | 2026 |
| JPH Aviation Services Ltd | Administrative & support | 2010 |
| JPH Building & Garden Services Ltd | Administrative & support | 2025 |
| JPL Groundwork Services Limited | Construction | 2017 |
| JPN Automotives Ltd | Wholesale & retail | 2026 |
| JPO BIM Services Limited | Professional & scientific | 2026 |
| JPP 24-7 Healthcare Ltd | Health & social care | 2023 |
| JPR Housing Ltd | Real estate | 2022 |
| JPR Roofing Limited | Construction | 2012 |