| Jadey Properties Ltd | Real estate | 2018 |
| Jadwiga Haden Trading Limited | Professional & scientific | 2019 |
| JAF Solutions Limited | Construction | 2025 |
| JAF Studio Ltd | Professional & scientific | 2022 |
| Jaff 93 Ltd | Wholesale & retail | 2025 |
| Jaff Empire Limited | Real estate | 2019 |
| Jaffas Hair CUT Ltd | Other services | 2025 |
| Jafx Capital Ltd | Financial services | 2021 |
| JAG Asset Management Ltd | Real estate | 2022 |
| JAG Capital Management Limited | Administrative & support | 2020 |
| JAG Drylining Ltd | Construction | 2024 |
| JAG Group Holdings Ltd | Professional & scientific | 2022 |
| JAG Key Advisory Limited | Professional & scientific | 2022 |
| JAG Resources Ltd | Real estate | 2022 |
| JAG Services (NW) Ltd | Construction | 2025 |
| Jaga Construction (North West) Ltd | Construction | 2018 |
| Jaga Developments (London) Ltd | Construction | 2019 |
| Jaga Group Development Ltd | Construction | 2017 |
| Jagged Edge (Whiston) Ltd | Other services | 2025 |
| Jago Majestic Limited | Information & communication | 2016 |
| Jagota Golf Travel Ltd | Administrative & support | 2025 |
| Jagota Holdings Ltd | Financial services | 2026 |
| Jagparts Europe Limited | Wholesale & retail | 2012 |
| Jags Building and Development Company Limited | Construction | 2004 |
| Jags Developments Ltd | Construction | 2013 |
| Jaguson Skills Ltd | Extraterritorial | 2014 |
| JAH Productions Limited | Information & communication | 2022 |
| JAH Solutions Ltd | Professional & scientific | 2022 |
| JAI Kudo Group Limited | Wholesale & retail | 2016 |
| Jain Healthcare Ltd | Education | 2021 |
| Jain Property Holding Ltd | Real estate | 2024 |
| Jaja Thai Ltd | Hospitality | 2018 |
| Jajd Properties Ltd | Real estate | 2022 |
| JAK Property Limited | Real estate | 2016 |
| Jake & Josh Ltd | Real estate | 2026 |
| Jakesville Studios Ltd | Professional & scientific | 2016 |
| JAL Rope Access Technicians Limited | Manufacturing | 2014 |
| Jalm Limited | Households | 2022 |
| JAM Care Services Ltd | Health & social care | 2026 |
| JAM Lifting Ltd | Construction | 2024 |
| JAM Property & Developments Ltd | Real estate | 2020 |
| JAM Property Projects Ltd | Real estate | 2022 |
| JAM Tea Rooms Limited | Hospitality | 2015 |
| Jam-Y-Digs Ltd | Real estate | 2026 |
| Jamac Property Services Limited | Real estate | 2025 |
| Jamaica Store Ltd | Wholesale & retail | 2026 |
| Jamaica Street Properties Limited | Real estate | 2021 |
| Jamal Bukhari Ltd | Wholesale & retail | 2025 |
| Jamals Food Distribution Ltd | Wholesale & retail | 2018 |
| JAMBO51 Ltd | Construction | 2023 |
| Jameliawl Ltd | Administrative & support | 2021 |
| Jameos Auto Services and Recovery Ltd | Wholesale & retail | 2026 |
| James & Patrick Boyd Ltd | Real estate | 2016 |
| James and Kieran Properties Ltd | Real estate | 2024 |
| James AR Smith Property Investment Ltd | Real estate | 2020 |
| James Barrington Limited | Education | 2013 |
| James Battle CIC | Hospitality | 2022 |
| James Begley Limited | Other services | 2015 |
| James Begley Properties Ltd | Real estate | 2019 |
| James Begley Training Academy Ltd | Education | 2021 |
| James Bulger Memorial Trust Limited | Hospitality | 2010 |
| James Charles Properties Ltd | Real estate | 2022 |
| James Clarke Morland Limited | Construction | 2019 |
| James Conning Consulting Ltd | Professional & scientific | 2024 |
| James Coulson Joinery Ltd | Construction | 2019 |
| James Crisp Digital Limited | Information & communication | 2014 |
| James Davies Transport Ltd | Transport & logistics | 2018 |
| James Development Group Ltd | Real estate | 2018 |
| James Driscoll Homes Limited | Construction | 2016 |
| James Financial Services Limited | Financial services | 2025 |
| James Foley Co Ltd | Transport & logistics | 2022 |
| James FOY Group Ltd | Construction | 2014 |
| James H Properties Ltd | Real estate | 2025 |
| James Hernandez and Associates Ltd | Administrative & support | 2020 |
| James Lyon & Co Limited | Health & social care | 2007 |
| James Media Ltd | Arts & recreation | 2024 |
| James Murphy Mens Hair Ltd | Other services | 2018 |
| James Nolan Construction Ltd | Construction | 2010 |
| James Nolan Electrical Telecoms Ltd | Information & communication | 2019 |
| James Nolan Ltd | Construction | 2019 |
| James Ormsby Limited | Professional & scientific | 2014 |
| James Quinn Associates Limited | Professional & scientific | 1991 |
| James Roofing (NW) Ltd | Construction | 2013 |
| James Sawden Limited | Construction | 2021 |
| James Stack Photography Ltd | Professional & scientific | 2023 |
| James Stott & Sons (Electrical) Limited | Administrative & support | 1936 |
| James Strange and Company Limited | Transport & logistics | 1954 |
| James Ward Counselling Ltd | Health & social care | 2020 |
| James Whitaker & Sons (Nurserymen) Limited | Wholesale & retail | 1913 |
| Jamescape Limited | Information & communication | 2020 |
| Jameslloydamz Limited | Transport & logistics | 2025 |
| Jameson Builders North West Limited | Construction | 2020 |
| Jameson Consult Limited | Construction | 2011 |
| JAMGAN4 Ltd | Administrative & support | 2014 |
| Jamie Carragher Limited | Professional & scientific | 2012 |
| Jamie Johnston Inspection Services Ltd | Construction | 2025 |
| Jamie Mullholland Ltd | Hospitality | 2005 |
| Jamjas Siblings Care Service Limited | Health & social care | 2026 |
| Jamjoe Ltd | Professional & scientific | 2025 |
| Jamlow Ltd | Administrative & support | 2026 |