| Janany's Sweet Treats Limited | Hospitality | 2025 |
| Janda Transport Ltd | Transport & logistics | 2025 |
| Jandu Property Group Ltd | Real estate | 2025 |
| Jandu Transport Limited | Transport & logistics | 2007 |
| Jangosupermarket Ltd | Wholesale & retail | 2025 |
| Jangra Transport Ltd | Transport & logistics | 2021 |
| Janisz Ltd | Transport & logistics | 2012 |
| Jannat Driveways Ltd | Construction | 2025 |
| Janro Limited | Manufacturing | 2021 |
| Jansons Bilding Constructions Ltd | Administrative & support | 2016 |
| Japji Transport Ltd | Transport & logistics | 2025 |
| Japsahib Ltd | Transport & logistics | 2025 |
| JAR 24 Limited | Financial services | 2025 |
| Jara Security Ltd | Administrative & support | 2025 |
| Jardin Electrical Limited | Construction | 2006 |
| Jarex Transport Ltd | Transport & logistics | 2016 |
| Jarral Investments LLP | | 2024 |
| Jars B Ltd | Real estate | 2019 |
| JAS and Sarb Property Investments Ltd | Real estate | 2024 |
| JAS G Fitness Ltd | Arts & recreation | 2025 |
| JAS Haulage Ltd | Transport & logistics | 2018 |
| JAS Stores and Solutions Ltd | Wholesale & retail | 2026 |
| Jasaitis Ltd | Construction | 2018 |
| Jasc Investments Limited | Real estate | 2024 |
| Jase Metals & Waste Limited | Water & waste | 2008 |
| Jaskirat Builders Ltd | Construction | 2019 |
| Jasmine Auto Ltd | Wholesale & retail | 2026 |
| Jason Cadman Agencies Limited | Wholesale & retail | 2006 |
| Jaspal Logistics Limited | Transport & logistics | 2026 |
| Jassal Procurement Consultants Limited | Information & communication | 2022 |
| Jassal Studio Ltd | Information & communication | 2022 |
| Jasspreet Ltd | Construction | 2026 |
| Jasstaj Construction Ltd | Construction | 2018 |
| Jas’S School of Spice Ltd | Wholesale & retail | 2026 |
| Jate Automotive Limited | Wholesale & retail | 2015 |
| Jats Transport Ltd | Transport & logistics | 2025 |
| Jatt Transport Ltd | Transport & logistics | 2019 |
| Java Consulting Limited | Construction | 2024 |
| Javadock Limited | Health & social care | 2020 |
| Javedai Ltd | Information & communication | 2025 |
| Javi Transport Ltd | Transport & logistics | 2023 |
| Jawanda Holdings Limited | Financial services | 2025 |
| Jawns LLP | | 2024 |
| Jaxx Performance Labs Ltd | Information & communication | 2025 |
| JAY 42 Ltd | Other services | 2020 |
| JAY and Slim Ltd | Hospitality | 2018 |
| JAY Coffee & Muffins Limited | Wholesale & retail | 2009 |
| JAY ENN Ltd | Administrative & support | 2018 |
| JAY Steel (Midlands) Limited | Wholesale & retail | 2007 |
| JAY Swingler Ltd | Arts & recreation | 2021 |
| Jay's Electrical Services Limited | Construction | 2019 |
| Jay's Trucks Ltd | Transport & logistics | 2017 |
| Jayannaj Ltd | Administrative & support | 2021 |
| Jaydylan Properties Limited | Real estate | 2025 |
| Jayhenz Limited | Hospitality | 2026 |
| Jayhenz Properties Ltd | Real estate | 2025 |
| Jayjay Nuga Enterprise Limited | Agriculture & fishing | 2020 |
| Jaymostudios Ltd | Professional & scientific | 2020 |
| Jaynmaro Marketing Ltd | Wholesale & retail | 2010 |
| Jays Health and Fitness UK Limited | Wholesale & retail | 2018 |
| Jaysmenu Ltd | Health & social care | 2025 |
| Jaywork Ltd Ltd | Wholesale & retail | 2025 |
| Jaza Medics Ltd | Health & social care | 2025 |
| Jazz Gill Transport Ltd | Transport & logistics | 2016 |
| Jazzily Podiatry & Chiropody Ltd | Health & social care | 2011 |
| JB Auto Security Ltd | Wholesale & retail | 2026 |
| JB Management Consultancy Ltd | Financial services | 2018 |
| JB MH Ltd | Wholesale & retail | 2025 |
| JB Potteries Ltd | Wholesale & retail | 2025 |
| JB Wilkes Ltd | Professional & scientific | 2020 |
| JBD Venture Services Limited | Wholesale & retail | 2020 |
| JBH Property Group Ltd | Real estate | 2026 |
| JBR Properties Birmingham Ltd | Real estate | 2019 |
| JBS 2 MAN Delivery Ltd | Transport & logistics | 2023 |
| JC Building Services Holdings Ltd | Real estate | 2024 |
| JC Building Services Ltd | Construction | 2016 |
| JC Fuels Limited | Wholesale & retail | 2019 |
| JC Motors Body Shop Ltd | Professional & scientific | 2026 |
| JC Properties Midlands Ltd | Real estate | 2019 |
| JC Transporting Ltd | Transport & logistics | 2025 |
| JC York Lettings Limited | Real estate | 2024 |
| Jc's Indian Bar & Grill Ltd | Hospitality | 2026 |
| Jc.Artwell Enterprise Ltd | Transport & logistics | 2025 |
| JCC Contracts Limited | Construction | 2017 |
| JCC Management Limited | Construction | 2017 |
| JCG Fashion Ltd | Wholesale & retail | 2014 |
| JCL Property Services Limited | Construction | 2026 |
| JCM Group Limited | Financial services | 2021 |
| JCM Properties Midlands Limited | Real estate | 2019 |
| JCN Company Limited | Health & social care | 2018 |
| JCS CAD Design Ltd | Professional & scientific | 2021 |
| JD Cakebox (Stourbridge) Limited | Wholesale & retail | 2022 |
| JD Fabrications Welding Company Ltd | Manufacturing | 2020 |
| JD Financial Planning Ltd | Financial services | 2014 |
| JD Lounges Ltd | Hospitality | 2018 |
| JD Mewp Services Ltd | Professional & scientific | 2021 |
| JD Properties 22 Limited | Real estate | 2022 |
| JD Services & Maintenance Ltd | Construction | 2022 |
| JD Talent Stream Ltd | Professional & scientific | 2011 |
| JD95 Ltd | Administrative & support | 2019 |