| Isrh Technologies Limited | Construction | 2025 |
| Istanbul Barbers HFD Limited | Other services | 2022 |
| ISW KT Ltd | Health & social care | 2024 |
| IT Direct Ltd | Wholesale & retail | 2014 |
| IT Tiles Limited | Wholesale & retail | 2024 |
| It's a Vibe Limited | Wholesale & retail | 2023 |
| Ital Trans Ltd | Transport & logistics | 2018 |
| Italian Tile Group Ltd | Wholesale & retail | 2026 |
| Italian Tiles Online Ltd | Other services | 2018 |
| ITI Tyres Ltd | Wholesale & retail | 2026 |
| Itooka Design Limited | Wholesale & retail | 2025 |
| ITS Your PA Limited | Administrative & support | 2013 |
| Ives Construction Limited | Construction | 2021 |
| IVY Aesthetics Ltd | Health & social care | 2021 |
| IVY International Ltd | Other services | 2007 |
| Ixta Ltd | Information & communication | 2022 |
| J & a Building & Joinery Ltd | Construction | 2024 |
| J & a Design Consultancy Ltd | Professional & scientific | 2024 |
| J & G Property Holdings Ltd | Real estate | 2019 |
| J & J Cooling Ltd | Construction | 2026 |
| J & R Electrical (Halifax) Limited | Construction | 2000 |
| J & S Holdings (Yorkshire) Limited | Wholesale & retail | 2024 |
| J a Spence Ltd | Financial services | 2014 |
| J B Building Services Design Limited | Professional & scientific | 2015 |
| J Baker Building Ltd | Other services | 2025 |
| J Bell Consultants Ltd | Professional & scientific | 2022 |
| J Bulgacs Holdings Ltd | Real estate | 2022 |
| J C Executive Cleaning Ltd | Administrative & support | 2022 |
| J Cockroft Property Limited | Real estate | 2019 |
| J D Halligan Limited | Wholesale & retail | 2017 |
| J D Lumb Consultancy Limited | Information & communication | 2012 |
| J D Wilkinson Ltd | Extraterritorial | 2004 |
| J E Barlow Chimney Sweep Limited | Administrative & support | 2020 |
| J E Barlow Stove Install Limited | Administrative & support | 2020 |
| J E Kendall Education Finance Ltd | Professional & scientific | 2025 |
| J E Mccabe & Sons Ltd | Real estate | 2026 |
| J F Plant and Formwork Hire Limited | Administrative & support | 2023 |
| J Fairbank Construction Ltd | Construction | 2020 |
| J Fradgley Joinery Limited | Construction | 2022 |
| J Harker Limited | Professional & scientific | 2020 |
| J Holden Joinery & Shopfitting Ltd | Construction | 2025 |
| J Johnson Consultants Ltd | Professional & scientific | 2026 |
| J M Developments (Halifax) Limited | Construction | 2020 |
| J Mallinson Ltd | Manufacturing | 2009 |
| J Moore Building and Plastering Services Ltd | Construction | 2021 |
| J N Dixon Consulting Limited | Other services | 2016 |
| J Rayner Properties Limited | Real estate | 2015 |
| J Trewhitt Limited | Construction | 2014 |
| J Tynan Joinery Limited | Construction | 2021 |
| J Willmott Commercials Ltd | Wholesale & retail | 2025 |
| J&A Supplies Ltd | Wholesale & retail | 2020 |
| J&C Dobson Building Services Ltd | Construction | 2018 |
| J&F Property Investments Limited | Real estate | 2023 |
| J&J Sunny Moon Ltd | Wholesale & retail | 2023 |
| J&S (NW) Limited | Real estate | 2024 |
| J. & C. Joel Limited | Manufacturing | 1978 |
| J. a. Parker Contractors Limited | Construction | 2004 |
| J. Ephraimson Ltd. | Extraterritorial | 1981 |
| J. Hillas & Sons (Holdings) Limited | Professional & scientific | 2000 |
| J. Swire & SON Limited | Wholesale & retail | 2003 |
| J. V. Models Limited | Wholesale & retail | 2009 |
| J.And G.Ainley(Towbars)Limited | Wholesale & retail | 1972 |
| J.C Pipework Services Ltd | Construction | 2026 |
| J.L Electrical Services (West Yorkshire) Ltd | Construction | 2025 |
| J.W.S. Services Limited | Health & social care | 2009 |
| J2 Hardware Limited | Wholesale & retail | 2015 |
| J2B Couriers Ltd | Transport & logistics | 2024 |
| J3 Joinery Ltd | Construction | 2024 |
| J3 Strategy Limited | Information & communication | 2023 |
| Jaben Trade Co., Limited | Wholesale & retail | 2025 |
| JAC Consultants (2008) Ltd | Professional & scientific | 2008 |
| Jack Fielden Joiners Limited | Extraterritorial | 2023 |
| Jack Hillas & Sons Limited | Wholesale & retail | 1961 |
| Jack Moro Limited | Health & social care | 2017 |
| Jack Waddington Timber Merchants Limited | Wholesale & retail | 2019 |
| Jack's Joinery Services Limited | Construction | 2019 |
| Jackson Building Developments Limited | Construction | 2019 |
| Jadent Financial Limited | Financial services | 2024 |
| JAG Enterprises Limited | Health & social care | 2017 |
| Jagger Construction Services Limited | Construction | 2008 |
| Jagger Green Properties Ltd | Real estate | 2022 |
| Jago J a Limited | Arts & recreation | 2008 |
| Jahlight Community Project Limited | Health & social care | 2019 |
| Jaja Photography Ltd | Professional & scientific | 2019 |
| Jake Richmond Plumbing and GAS Ltd | Construction | 2026 |
| Jakhya Ltd | Hospitality | 2019 |
| JAM Plastering Halifax Ltd | Construction | 2024 |
| Jam-Jy Properties Ltd | Real estate | 2022 |
| Jamaal Hamza Ltd | Wholesale & retail | 2026 |
| James and Reuben Limited | Health & social care | 2008 |
| James Atkinson Anaesthetics Ltd | Health & social care | 2018 |
| James C Halstead (Surgery) Ltd | Health & social care | 2013 |
| James Chambers (Timber Merchants) Limited | Wholesale & retail | 1943 |
| James Jackson (Halifax) Limited | Wholesale & retail | 1928 |
| James Julier Ltd | Arts & recreation | 2025 |
| James Mason Court Management Company Limited | Households | 2000 |
| James Melia Photographers Ltd | Arts & recreation | 2014 |
| Jamocha Coffee Lounge Ltd | Hospitality | 2019 |
| JAN Hair and Beauty Hairdresser Ltd | Wholesale & retail | 2026 |
| Jane Cooper Limited | Health & social care | 2006 |