| JM Bespoke Property Services Ltd | Real estate | 2024 |
| JM Brickwork Services Ltd | Construction | 2024 |
| JM Leisure Limited | Hospitality | 2012 |
| JMB Evolution Ltd | Construction | 2020 |
| Jmcd Developments (Yorkshire) Limited | Construction | 2026 |
| Jmcd Developments Limited | Construction | 2019 |
| Jmcd Properties Ltd | Real estate | 2025 |
| JMD Kapow Ltd | Real estate | 2014 |
| JMM Engineering (Halifax) Ltd | Manufacturing | 2012 |
| Jmmk Projects Ltd | Construction | 2015 |
| JMS Creations Limited | Construction | 2017 |
| JNR Projects Ltd | Construction | 2022 |
| JO Small Limited | Health & social care | 2008 |
| Joanne Wright Physiotherapy Services Ltd | Health & social care | 2015 |
| Jobs in White Ltd | Health & social care | 2015 |
| JOE Bailey Limited | Wholesale & retail | 2019 |
| JOE Bowmer Ltd | Real estate | 2025 |
| JOE Dean and Sons (Haulage) Limited | Administrative & support | 1961 |
| Joelle Couture Aesthetics Ltd | Other services | 2022 |
| Johal Brothers Halifax Limited | Wholesale & retail | 2013 |
| Johal Empire Limited | Real estate | 2013 |
| Johal Housing Ltd | Real estate | 2018 |
| Johals News Ltd | Wholesale & retail | 2025 |
| John & Randolph Bottomley Limited | Wholesale & retail | 1979 |
| John C Nelson Construction Limited | Construction | 2021 |
| John Denwood Consulting Limited | Professional & scientific | 2012 |
| John Handley (Construction) Ltd | Construction | 2008 |
| John L Brierley Arts & Crafts Ltd | Wholesale & retail | 2018 |
| John Laithwaite Investments Limited | Administrative & support | 2010 |
| John Laithwaite Partners LLP | | 2011 |
| John Maguire (Halifax) Limited | Wholesale & retail | 2004 |
| John MAY (Surgery) Ltd | Health & social care | 2014 |
| John Pawson (Holdings) Limited | Financial services | 2013 |
| John Pawson Limited | Professional & scientific | 2009 |
| John Stuart & Co.Limited | Financial services | 1900 |
| John Veitch Limited | Wholesale & retail | 1987 |
| John Winter & Company Limited | Wholesale & retail | 1963 |
| Johnnys Mobile Tyres Ltd | Wholesale & retail | 2020 |
| Johnston Memorials Ltd | Manufacturing | 2021 |
| Joint Specialists Ltd | Health & social care | 2025 |
| Jojko Transport Ltd | Transport & logistics | 2020 |
| Jolly Recycling Limited | Wholesale & retail | 2019 |
| Jonah Martin Limited | Financial services | 2015 |
| Jonathan M Dawson Ltd | Construction | 2013 |
| Jones Property Rentals Limited | Real estate | 2025 |
| Joseph & Khan Solicitors Limited | Professional & scientific | 2017 |
| Joseph Chance Limited | Wholesale & retail | 2017 |
| Journeyhub Travels & Money Transfers Ltd | Administrative & support | 2025 |
| Jowetts Holding (Halifax) Limited | Administrative & support | 2016 |
| Joy X Capital Ltd | Financial services | 2024 |
| Joyce Prvt Limited | Health & social care | 2015 |
| Joytoshop Limited | Wholesale & retail | 2019 |
| JP Drum Products Limited | Wholesale & retail | 2014 |
| JP Rossi Ltd | Professional & scientific | 1998 |
| JPS Transport Solutions Limited | Transport & logistics | 2019 |
| JPW Associates Ltd | Construction | 2018 |
| JR Mobile Detailing Ltd | Wholesale & retail | 2022 |
| JR Supply Ltd | Wholesale & retail | 2025 |
| JRC Flooring UK Ltd | Construction | 2021 |
| JRH Accountancy & Taxation Ltd | Professional & scientific | 2011 |
| JRR Solutions Ltd | Professional & scientific | 2023 |
| JRS Electrical Solutions Ltd | Construction | 2020 |
| JRT Joinery & Roofing Services Ltd | Construction | 2018 |
| JRW Stove Installations Limited | Construction | 2023 |
| JS Information Governance Limited | Administrative & support | 2017 |
| JS Plumbing Solutions Limited | Construction | 2025 |
| Jsbl Ltd | Education | 2025 |
| Jside Ltd | Professional & scientific | 2022 |
| JT Services Group Limited | Extraterritorial | 2019 |
| JTC Commercial Properties Limited | Real estate | 2011 |
| JTF Fabrications Limited | Manufacturing | 2012 |
| JTS Joinery Services Limited | Construction | 2015 |
| JTS Plumbing & Heating Limited | Administrative & support | 2017 |
| Judson&Judson Counselling Ltd | Health & social care | 2025 |
| Juiced OUT HX Ltd | Manufacturing | 2025 |
| Jules Carey Limited | Professional & scientific | 2011 |
| Julia C Limited | Hospitality | 2023 |
| Julie Archer Trainer & Consultant Ltd | Professional & scientific | 2012 |
| Jump Properties (UK) Limited | Real estate | 2020 |
| Junction Auto Care Ltd | Wholesale & retail | 2018 |
| Juneau I.T Limited | Information & communication | 2015 |
| Juno (Property) Ltd | Real estate | 2004 |
| Juno Software Ltd | Information & communication | 2008 |
| Just - EPC - Halifax Limited | Administrative & support | 2012 |
| Just Cars and Vans Limited | Wholesale & retail | 2019 |
| Just Delivery Ltd | Professional & scientific | 2021 |
| Just Dwellings Ltd | Real estate | 2016 |
| Just Gaia Ltd | Wholesale & retail | 2019 |
| Just Halal Fresh Ltd | Wholesale & retail | 2026 |
| Just Travelling Ltd | Administrative & support | 2024 |
| JUSTGRAZE21 Limited | Hospitality | 2026 |
| JV Living Limited | Financial services | 2025 |
| JVL Holdings Limited | Wholesale & retail | 2005 |
| JVL International Limited | Wholesale & retail | 2015 |
| JW Coaching Services Ltd | Education | 2026 |
| JW Site Services Ltd | Construction | 2022 |
| JWB Research Ltd | Professional & scientific | 2025 |
| JWR Engineering Limited | Manufacturing | 2002 |
| K & a Healthcare Ltd | Wholesale & retail | 2019 |
| K & I Deal Sourcing Ltd | Real estate | 2025 |