| Jolorn Properties Limited | Construction | 2018 |
| JON Dawson & Co Limited | Professional & scientific | 2011 |
| JON JON Building Services Ltd | Construction | 2014 |
| JON Parker Consultancy Ltd | Professional & scientific | 2024 |
| Jonac Base Services (UK) Limited | Transport & logistics | 2013 |
| Jonathan COX Limited | Construction | 2014 |
| Jonathan Fitzpatrick Village and Country Homes LLP | | 2021 |
| Jonathan M Smith Limited | Professional & scientific | 2011 |
| Jonathan Paling Limited | Wholesale & retail | 2018 |
| Jonava Bidco Limited | Financial services | 2024 |
| Jonel Limited | Health & social care | 2024 |
| Jones & Co(Nottingham),Limited | Wholesale & retail | 1923 |
| Jones & Sons Lodges LLP | | 2023 |
| Jones Financial Accountants Ltd | Professional & scientific | 2025 |
| Joniroke Enterprises Limited | Agriculture & fishing | 1973 |
| Jonna Investments Ltd | Financial services | 2025 |
| Jonny Sponge Cleaning Ltd | Construction | 2025 |
| Jonwankwo Limited | Health & social care | 2022 |
| Jooltec Limited | Information & communication | 2026 |
| JOP Arts CIC | Arts & recreation | 2024 |
| Joraij Enterprise Ltd | Wholesale & retail | 2026 |
| Jordan Benjamin Associates Ltd | Professional & scientific | 2005 |
| Jordan Carter Ltd | Administrative & support | 2024 |
| Jordan Court Ltd | Real estate | 2012 |
| Jordan GOT Wood Ltd | Wholesale & retail | 2019 |
| Jordan James ARB Ltd | Agriculture & fishing | 2025 |
| Jordan James Fothergill Ltd | Information & communication | 2024 |
| Jordan Textile Limited | Wholesale & retail | 2018 |
| Jordan UK Textile Ltd | Wholesale & retail | 2024 |
| Jordan's Recycling Ltd | Water & waste | 2016 |
| Jordonscatering Ltd | Hospitality | 2025 |
| Joreev Limited | Information & communication | 2016 |
| Jorge Alvaro DE Castro Torres Limited | Health & social care | 2014 |
| Joris Ltd | Wholesale & retail | 2022 |
| Jorvik I.T. Limited | Information & communication | 2015 |
| Josan (Midlands) Ltd | Transport & logistics | 2019 |
| Jose & Fran Care Ltd | Health & social care | 2019 |
| Jose Maria Diosdado Cano Limited | Health & social care | 2021 |
| Josef Architecture Limited | Professional & scientific | 2007 |
| Josef Developments Limited | Real estate | 1999 |
| Joseph A.Hey & SON Limited | Other services | 1952 |
| Joseph and Kurian Limited | Health & social care | 2014 |
| Joseph Clark Collection Management Ltd | Arts & recreation | 2023 |
| Joseph Jones Professional Horticulture Limited | Administrative & support | 2015 |
| Joseph O'Connell Funeral Service Limited | Extraterritorial | 2011 |
| Joseph Truman & Company (1924) Limited | Professional & scientific | 1924 |
| Josephine Pearse Consulting Limited | Professional & scientific | 2024 |
| Josephine's Tea Lounges Ltd | Hospitality | 2020 |
| Josery Textiles Limited | Other services | 1939 |
| Joshirl Ltd | Financial services | 2018 |
| Joshman Ltd | Financial services | 2023 |
| Joshua Ellis Music Ltd | Information & communication | 2022 |
| Joshua Judah Company Ltd | Health & social care | 2016 |
| Joshua Tree Limited | Other services | 2002 |
| Joshua's Kerala Foods Ltd | Wholesale & retail | 2025 |
| Josie's Emporium Ltd | Wholesale & retail | 2022 |
| Jova Skin Micro Plasma Limited | Other services | 2020 |
| Jowett Carpets Limited | Wholesale & retail | 2006 |
| Jowett Holdings Limited | Financial services | 2017 |
| Joy Forty Five Ltd | Professional & scientific | 2025 |
| Joy Phido International Limited | Administrative & support | 2022 |
| Joy Property Management Limited | Construction | 2023 |
| Joy Rejuvenates CIC | Education | 2025 |
| Joy's Green Group Ltd | Administrative & support | 2026 |
| JOY2CARE Ltd | Health & social care | 2013 |
| Joyce Safety Ltd | Health & social care | 2025 |
| Joyces Choice Ltd | Real estate | 2022 |
| Joydrop Ltd | Wholesale & retail | 2025 |
| Joyfredwil Healthcare Ltd | Health & social care | 2012 |
| Joyful Enterprise Limited | Real estate | 2012 |
| Joyful Shine Cleaning Company Limited | Administrative & support | 2025 |
| Joyful WOK Restaurant Ltd | Hospitality | 2025 |
| JP 6511 Limited | Health & social care | 2023 |
| JP Agricultural Limited | Agriculture & fishing | 2024 |
| JP and Family Property Holdings Ltd | Real estate | 2026 |
| JP Brakes Ltd | Wholesale & retail | 2022 |
| JP Developments 6 Limited | Real estate | 2025 |
| JP Electrical Solutions Limited | Manufacturing | 2019 |
| JP Holdings Midland Ltd | Hospitality | 2021 |
| JP Imperium Ltd | Wholesale & retail | 2024 |
| JP Property Rental Limited | Real estate | 2021 |
| JP Property Services (E.Midlands) Limited | Real estate | 2018 |
| JP Rail Construction Ltd | Construction | 2024 |
| JP Teltech Ltd | Information & communication | 2019 |
| JPA (UK) Law Firm Ltd | Professional & scientific | 1998 |
| Jpas Limited | Professional & scientific | 2002 |
| JPC Capital Limited | Other services | 2018 |
| JPC Plant & Safety Limited | Construction | 2016 |
| JPC UK Holdings Ltd | Financial services | 2023 |
| JPC UK Property Ltd | Real estate | 2023 |
| JPD Civils Limited | Construction | 2017 |
| JPD Maintenance Services Ltd | Construction | 2018 |
| JPD.1 Limited | Professional & scientific | 2013 |
| Jpeg Studio Ltd | Professional & scientific | 2025 |
| Jpengosteakhouse Ltd | Hospitality | 2025 |
| Jpfpro Limited | Professional & scientific | 2021 |
| JPG Group (Midlands) Ltd | Real estate | 2021 |
| Jpgo Ltd | Extraterritorial | 2022 |
| JPH Medical Services Limited | Health & social care | 2023 |
| JPH Property Holdings Limited | Real estate | 2025 |