| Jnshopfitters Limited | Manufacturing | 2013 |
| Jntpb Investments Limited | Real estate | 2022 |
| JO Events Ltd | Hospitality | 2020 |
| JO Rudolphy Limited | Information & communication | 2013 |
| Joanna Adamiec Ltd | Manufacturing | 2019 |
| Joanna Investments Ltd | Real estate | 2016 |
| Joaquim Builders Limited | Construction | 2025 |
| Joarder Ltd | Health & social care | 2010 |
| JOB Zone Ltd | Construction | 2020 |
| Joba Foods Ltd | Hospitality | 2022 |
| Jobean Limited | Professional & scientific | 2012 |
| Jobs DE Globe Ltd | Administrative & support | 2020 |
| Jobspace Europe Limited | Administrative & support | 2016 |
| Jodata Ltd | Information & communication | 2019 |
| JOE Posnett Consulting Ltd | Professional & scientific | 2026 |
| Joel Builders Ltd | Construction | 2024 |
| Joevic Security Services Ltd | Administrative & support | 2012 |
| JOF Security Services Ltd | Administrative & support | 2024 |
| Joffee Ltd | Information & communication | 2023 |
| Joginder Investments Ltd | Real estate | 2025 |
| Johal Property Management Ltd | Real estate | 2022 |
| Johal R S Limited | Professional & scientific | 2011 |
| Johal Screeding Ltd | Construction | 2024 |
| Johals Property Limited | Construction | 2014 |
| JOHIR1 Limited | Professional & scientific | 2023 |
| John & Grey Estate Ltd | Real estate | 2024 |
| John Best Limited | Wholesale & retail | 2018 |
| John Butler Souvenirs Limited | Wholesale & retail | 2017 |
| John Elbert Limited | Wholesale & retail | 2025 |
| John Energy Solution Ltd | Construction | 2021 |
| John Forbes Ltd | Transport & logistics | 2009 |
| John London Interiors Limited | Construction | 2018 |
| John Mengolli Trans Spedition Ltd | Transport & logistics | 2022 |
| John Nelson Press Ltd | Information & communication | 2022 |
| John.R Construction Group Ltd | Construction | 2025 |
| Johnny General Construction Ltd | Construction | 2025 |
| Johnny Johnston Music Limited | Information & communication | 1979 |
| Johnny Walls Ltd | Hospitality | 2026 |
| Johnny's Pizza Limited | Hospitality | 2018 |
| Johnson & Nicholas Properties Limited | Real estate | 2021 |
| Johnston Saffron Limited | Information & communication | 2023 |
| Johnstone Family Property Management Limited | Real estate | 2019 |
| Joinery JOE Ltd | Manufacturing | 2021 |
| Joint & Muscle Pain Solutions (Jmps) Ltd | Health & social care | 2024 |
| Joint Removals & Storage Ltd | Transport & logistics | 2023 |
| Joint Team Ltd | Construction | 2021 |
| Joitall Plaster Limited | Construction | 2022 |
| Joity Associates Ltd. | Wholesale & retail | 2011 |
| Jojene Trader Limited | Wholesale & retail | 2026 |
| Jokubauskas Construction Ltd Ltd | Construction | 2025 |
| Jolewis Industries Company Ltd | Administrative & support | 2010 |
| Joloh Limited | Professional & scientific | 2007 |
| Joma Gadgets Limited | Wholesale & retail | 2024 |
| Jomatech Limited | Wholesale & retail | 2023 |
| JON Sames Opticians Limited | Health & social care | 2004 |
| Jonathan Farquharson Property Limited | Real estate | 2024 |
| Jones Bespoke Furniture Limited | Manufacturing | 2018 |
| Jones Bespoke Interiors Ltd | Wholesale & retail | 2021 |
| Jonmo Ltd | Hospitality | 2024 |
| Jonny Walls Limited | Hospitality | 2026 |
| Jonnysoft Limited | Information & communication | 2016 |
| Jony Codes Limited | Information & communication | 2023 |
| Jony.K Construction Limited | Manufacturing | 2026 |
| Jora Group Limited | Wholesale & retail | 2025 |
| Jora Health Limited | Information & communication | 2014 |
| Jordan and SON (Forwarding) Limited | Transport & logistics | 1989 |
| Josan Bricks Ltd | Construction | 2023 |
| Joseph Anthony Ltd | Construction | 2026 |
| Joseph Fairmont Ltd | Professional & scientific | 2024 |
| Joseph Housing Limited | Real estate | 2017 |
| Joseph Properties Limited | Real estate | 2019 |
| Josfort Comfort Care Ltd | Health & social care | 2020 |
| Josh GAB Health Ltd | Other services | 2024 |
| Josh Properties Ltd | Real estate | 2006 |
| Josh Property Services Ltd | Real estate | 2019 |
| Josh Vantage Consulting Group Ltd | Professional & scientific | 2024 |
| Joslan Foods Limited | Hospitality | 2014 |
| Josuaconstruct Limited | Construction | 2025 |
| JOT Double Glazing Ltd | Construction | 2025 |
| Journey Care Systems Ltd | Information & communication | 2026 |
| Journey Health Ltd | Wholesale & retail | 2024 |
| Jovan Transport Ltd | Transport & logistics | 2020 |
| Joy Consult Conveyancing Ltd | Professional & scientific | 2024 |
| Joy Nest Ltd | Wholesale & retail | 2021 |
| Joybun Estates Ltd | Real estate | 2026 |
| Joyia International Ltd | Administrative & support | 2024 |
| Joyjiggle Limited | Information & communication | 2025 |
| Joyride Pictures Ltd | Information & communication | 2019 |
| Joys of Beauty Limited | Other services | 2012 |
| Joys SL Property Ltd | Real estate | 2025 |
| Jozad Ltd | Construction | 2026 |
| JP Builders & Decorator Ltd | Water & waste | 2013 |
| JP Concrete Service Ltd | Construction | 2023 |
| JP Construction Limited | Construction | 2021 |
| JP Investments (Essex) Ltd | Real estate | 2021 |
| JP Mohiv Investment Ltd | Real estate | 2024 |
| JP Periodontics Ltd | Health & social care | 2023 |
| JP VEG Ltd | Wholesale & retail | 2020 |
| Jp&K Property Limited | Real estate | 2020 |
| JPA Traders Ltd | Real estate | 2019 |