| Kenderby Holdings Ltd | Real estate | 2023 |
| Kendrion (UK) Limited | Wholesale & retail | 1973 |
| Kershaw & Kelly Holdings Ltd | Financial services | 2022 |
| Key Healthcare (ST. Helens) Limited | Health & social care | 2005 |
| Key Healthcare Limited | Health & social care | 2012 |
| Keyholeai Ltd | Administrative & support | 2023 |
| KG Fitness Ltd | Education | 2026 |
| KHA Consulting Limited | Professional & scientific | 2017 |
| KIK OFF Leagues Limited | Arts & recreation | 2021 |
| Kimberley (Yorkshire ) Ltd | Wholesale & retail | 2023 |
| Kimell Ltd | Other services | 2024 |
| KIN Body & Sole Limited | Health & social care | 2021 |
| Kingswood Private Clients Limited | Financial services | 2018 |
| Kirby & Associates Wealth Management Limited | Financial services | 2012 |
| Kirby Farm Limited | Real estate | 2025 |
| Kiroco Limited | Wholesale & retail | 2008 |
| Kirsty Ward Ltd | Professional & scientific | 2026 |
| Kizmit Solutions Ltd | Information & communication | 2014 |
| Klein & Sons Ltd | Information & communication | 2010 |
| Klhmed-Ed Ltd | Education | 2023 |
| Knaresborough Engineering (Yorkshire) Ltd | Manufacturing | 2011 |
| Knight Franchises Ltd | Administrative & support | 2015 |
| KOB Kitchens Ltd | Manufacturing | 2019 |
| Kortek Ltd | Wholesale & retail | 2021 |
| Kreftholdings Ltd | Hospitality | 2020 |
| KT Motor Works Ltd | Wholesale & retail | 2025 |
| Kudos Cycling Limited | Arts & recreation | 2016 |
| Kusto Ltd | Hospitality | 2025 |
| KWA (Aviation Solutions) Limited | Transport & logistics | 2020 |
| L Andrews Transport Ltd | Construction | 2019 |
| L&D Lets Limited | Real estate | 2004 |
| L&D Rentals and Lets Limited | Wholesale & retail | 1990 |
| L. Batley Holdings Limited | Professional & scientific | 1989 |
| LAA LAA Limited | Information & communication | 2023 |
| Labskin Limited | Professional & scientific | 2023 |
| Lagaz Ltd | Wholesale & retail | 2021 |
| Lambson Limited | Wholesale & retail | 1993 |
| Landmark Estates (NE) Ltd | Real estate | 2019 |
| Landmark Holdings (NE) Ltd | Real estate | 2020 |
| Landmark North Ltd | Wholesale & retail | 2021 |
| Landscape One Design Ltd | Construction | 2009 |
| Langcliffe Group Limited | Financial services | 2024 |
| Langcliffe International Employee Ownership Trustee Limited | Administrative & support | 2023 |
| Langcliffe International Limited | Financial services | 2012 |
| Langley LG Limited | Professional & scientific | 2024 |
| Langwith Development Partnership Limited | Construction | 2017 |
| Langwith Developments Ltd | Construction | 2015 |
| Langwith Grange Management Limited | Real estate | 2000 |
| Larkes Holdings Ltd | Financial services | 2026 |
| Lars Armstrong Building Consultancy Ltd | Professional & scientific | 2015 |
| Laudale Estate LLP | | 2013 |
| Laurel Court (Harrogate) Management Limited | Households | 1999 |
| Laverack Communications Limited | Professional & scientific | 2009 |
| Lawnkeeper Limited | Administrative & support | 2000 |
| Lawns House Management Co Ltd | Real estate | 2014 |
| LBH (2012) Limited | Professional & scientific | 2012 |
| Lcal Limited | Professional & scientific | 2015 |
| LDN Early Years Ltd | Education | 2013 |
| Lead Management System Limited | Information & communication | 2018 |
| Leading Operations Limited | Professional & scientific | 2023 |
| Leadit Limited | Information & communication | 2002 |
| Leads Administration Business Limited | Information & communication | 2021 |
| LEAPIN2LEARNING Ltd | Education | 2022 |
| Leaps & Bounds Gymnastics Club Ltd | Arts & recreation | 2016 |
| Learning Goal Ltd | Extraterritorial | 2023 |
| Lease Flat Management Co Limited | Real estate | 2011 |
| Leedman Ltd | Professional & scientific | 2017 |
| Leeds & District Clothing & Supply Co.Limited | Financial services | 1941 |
| Leeds Aesthetics Group Ltd | Health & social care | 2017 |
| Leeds City Physiotherapy Clinic Limited | Health & social care | 2016 |
| Leeds Community and Advocacy Service Community Interest Company | Health & social care | 2026 |
| Leeds Diocesan Learning Trust | Education | 2021 |
| Leeds Electrical Services Ltd | Construction | 2018 |
| Leeds Extensions Limited | Construction | 2017 |
| Leeds Facilities Management Ltd | Manufacturing | 2018 |
| Leeds Group Limited | Financial services | 1900 |
| Leeds M&E (Personnel) Ltd | Construction | 2018 |
| Leeds Mechanical and Electrical Services Ltd | Construction | 2018 |
| Leeds Shotokan Karate Club Ltd | Extraterritorial | 2019 |
| Leeds Sports Injury & Physiotherapy Clinic Limited | Health & social care | 2007 |
| Legato Marketing Limited | Administrative & support | 2008 |
| Lenmor Capital Limited | Financial services | 2025 |
| Leppington Ltd | Health & social care | 2011 |
| Lets Just BE Frank Ltd | Professional & scientific | 2020 |
| Leventhorpe Farm Ltd | Agriculture & fishing | 2026 |
| Leyburn Group Limited | Construction | 2024 |
| Leyburn Property Development Limited | Construction | 2024 |
| Leyburn Uppers Ltd | Real estate | 2024 |
| LEYBURN9B Limited | Real estate | 2026 |
| Libani Ltd | Real estate | 2019 |
| LIBERTY2803 Limited | Professional & scientific | 2011 |
| Life Plan Partners Limited | Financial services | 2025 |
| Lift Club Fitness Ltd | Other services | 2022 |
| Lift Club Wetherby Ltd | Other services | 2025 |
| Light Source International Ltd | Wholesale & retail | 2018 |
| Lighthouse Pizza Co Ltd | Hospitality | 2023 |
| Lightning Logistics International Ltd | Construction | 2017 |
| Limelight Lifestyle Consultancy Limited | Professional & scientific | 2020 |
| Limewood Business Park Management Company Limited | Real estate | 2003 |
| Linen Xcel Limited | Other services | 2024 |