| JS Property Services (Leeds) Limited | Real estate | 2024 |
| Jsar 37 Ltd | Information & communication | 2024 |
| JSB Sales and Marketing Ltd | Wholesale & retail | 2024 |
| JST Hospitality Ltd | Hospitality | 2024 |
| JT Development Solutions Limited | Education | 2010 |
| Jubbeducationalpsychology Limited | Education | 2025 |
| Junction 27 Motors Limited | Wholesale & retail | 2026 |
| Jupiter Home Solutions Ltd | Construction | 2025 |
| Just Houses Ltd | Real estate | 2024 |
| Just Waste Limited | Water & waste | 2025 |
| Justin Pook Theming Studio Ltd | Arts & recreation | 2018 |
| Jwgw Construction Limited | Construction | 2025 |
| Jwgw Lets Ltd | Hospitality | 2023 |
| Jwgw Property Investment Ltd | Construction | 2019 |
| JYM Designs Ltd | Information & communication | 2024 |
| K Hogg Accountancy Limited | Professional & scientific | 2014 |
| K&J Chippendale Limited | Professional & scientific | 2025 |
| K&N Accounting Services Ltd | Professional & scientific | 2022 |
| KAB Freight Ltd | Transport & logistics | 2021 |
| KAD Studios Ltd | Information & communication | 2021 |
| Kaiako Consulting Limited | Professional & scientific | 2023 |
| Kala Sangam Global Ltd | Education | 2024 |
| Kalamateyes Limited | Health & social care | 2010 |
| Kaleidoscope Psychology and Psychotherapy Ltd | Health & social care | 2020 |
| Kanton International Consultancy Services Limited | Financial services | 2010 |
| Karakata Enterprises Ltd | Wholesale & retail | 2025 |
| Karakousis Properties Ltd | Real estate | 2025 |
| Karra Bistro Ltd | Hospitality | 2025 |
| Karwan Traders Ltd | Wholesale & retail | 2026 |
| KAY9 Groom Room Ltd | Other services | 2020 |
| Kayedem Demolition Limited | Construction | 2013 |
| Kayedem Facilities Management Limited | Administrative & support | 2018 |
| KC25 Properties Limited | Real estate | 2025 |
| Kctec Limited | Wholesale & retail | 2016 |
| Kctec Trading Limited | Wholesale & retail | 2016 |
| KD Group (Yorkshire) Limited | Construction | 2024 |
| KE & Zhuo Ltd | Other services | 2017 |
| Keats Site Services Limited | Manufacturing | 2014 |
| Kendlmere Limited | Administrative & support | 2026 |
| Kent & Carington Limited | Administrative & support | 2026 |
| Kepler Holdings Ltd | Real estate | 2015 |
| Key Tech Services Ltd | Other services | 2020 |
| Keytech Managed Solutions Limited | Information & communication | 2013 |
| Khan Investments Partnership LLP | | 2022 |
| Kids Academy Limited | Health & social care | 1999 |
| Kindly Earth International Limited | Other services | 2022 |
| Kindly Earth Limited | Other services | 2021 |
| Kirkgateresidence Limited | Real estate | 2011 |
| Kirkstall Gate Ltd | Hospitality | 2017 |
| Kirkstall Gate Property Management Ltd | Real estate | 2024 |
| Kirkstallgate Apts Ltd | Real estate | 2022 |
| Kitchen Madlic Ltd | Wholesale & retail | 2025 |
| Kitsune Labs Ltd | Information & communication | 2025 |
| KKM Consultancy Ltd | Professional & scientific | 2021 |
| KKM Property Services Ltd | Real estate | 2024 |
| Klin Trading Ltd | Hospitality | 2024 |
| Koko Nails Limited | Other services | 2025 |
| Konekta TEL Limited | Information & communication | 2025 |
| Kova Coffee Ltd | Hospitality | 2026 |
| Kovenzo Ltd | Arts & recreation | 2025 |
| Kpan Properties Ltd | Real estate | 2019 |
| KPS Freeholds Ltd | Real estate | 2024 |
| Krios AI Ltd | Professional & scientific | 2024 |
| KSA Technologies Limited | Information & communication | 2024 |
| KSD Childcare Ltd | Health & social care | 2022 |
| KSS Marketing Limited | Administrative & support | 2016 |
| Kudu Products Limited | Wholesale & retail | 2003 |
| L & C PUB Services Ltd | Professional & scientific | 2024 |
| L Green Electrical Solutions Yorkshire Ltd | Construction | 2024 |
| L S Electrical (Yorkshire) Ltd | Energy | 2025 |
| L&P Investment Partnerships Ltd | Other services | 2024 |
| L&V Homes Ltd | Real estate | 2018 |
| L.D.T Limited | Other services | 2017 |
| L.J. Sinclair Limited | Construction | 2024 |
| Lacey Aesthetics Ltd | Education | 2021 |
| Lacuna Planning & Designs Ltd | Professional & scientific | 2021 |
| Lancaster IT Consulting Limited | Information & communication | 2024 |
| Lancaster Park 5/7 (Harrogate) Management Company Limited | Households | 2008 |
| Langan Consulting Ltd | Professional & scientific | 2014 |
| Langley Valves Limited | Professional & scientific | 2004 |
| Lantern Debt Recovery Services Limited | Financial services | 2008 |
| Lantern Portfolio Management Limited | Financial services | 2017 |
| Laura Jane Interiors Ltd | Professional & scientific | 2024 |
| Laws 4 Floors (Pudsey) Ltd | Construction | 2017 |
| LCM Transport Services Ltd | Transport & logistics | 2026 |
| LE Voyage Dining Experience Limited | Hospitality | 2026 |
| Lease Solutions Group Limited | Wholesale & retail | 2024 |
| LED Handrails.Com Ltd | Manufacturing | 2021 |
| Leeds and Bradford Boiler Company Limited(The) | Manufacturing | 1892 |
| Leeds and Bradford Model Boat Club Ltd | Arts & recreation | 2006 |
| Leeds Area Telugu Association | Other services | 2019 |
| Leeds Building Company Limited | Construction | 2022 |
| Leeds City Estate Holdings Ltd | Real estate | 2026 |
| Leeds Dart Shop Ltd | Wholesale & retail | 2025 |
| Leeds Fireplaces and Stoves Limited | Other services | 2013 |
| Leeds Heating Services Ltd | Construction | 2023 |
| Leeds LOG Burners and Fireplaces Limited | Wholesale & retail | 2021 |
| Leeds Render Systems Limited | Construction | 2019 |
| Legitech Group Ltd | Wholesale & retail | 2022 |
| Leigh House Facilities Management Limited | Real estate | 1992 |