| Horizon Game Limited | Agriculture & fishing | 2009 |
| Horleys (Yorkshire) Ltd | Construction | 2016 |
| Hudd Engineering Ltd | Manufacturing | 2016 |
| Humber Barges Limited | Transport & logistics | 1994 |
| Hung Moey Ltd | Hospitality | 2025 |
| Hunton Farms Limited | Agriculture & fishing | 2012 |
| HURD3 Limited | Professional & scientific | 2023 |
| Hydrographics Limited | Manufacturing | 2016 |
| Hype Marketing UK Limited | Other services | 2013 |
| I & D Bell Ltd | Real estate | 2021 |
| IAN Beaumont Electrical Contractors Ltd | Construction | 2022 |
| Ideal Care (North) Limited | Health & social care | 1998 |
| Ielt Limited | Education | 2016 |
| IG Trading Northeast Ltd | Wholesale & retail | 2025 |
| IN Demand Properties Ltd | Real estate | 2019 |
| Indigo Hub Ltd | Education | 2021 |
| Infrared Replacing GAS Ltd | Energy | 2020 |
| Inspiration Brand Sales Solutions Ltd | Wholesale & retail | 2013 |
| Inspirational Leadership Limited | Professional & scientific | 2006 |
| Inspirations Learning & Development Limited | Professional & scientific | 2003 |
| Intelligent Bioinformatics Limited | Manufacturing | 2023 |
| Internet Plumbers Ltd | Information & communication | 2024 |
| Internet Tubes Ltd | Information & communication | 2024 |
| Islebeck Holdings Ltd | Financial services | 2017 |
| Isobel Peters Consulting Limited | Professional & scientific | 2020 |
| Italian Legends Ltd | Wholesale & retail | 2020 |
| J & L Winspear Ltd | Agriculture & fishing | 2020 |
| J & R Farm Supplies Ltd | Wholesale & retail | 2018 |
| J B & R Consultants Limited | Professional & scientific | 2021 |
| J Binks & Sons Limited | Construction | 2020 |
| J F Charlton and Company Limited | Manufacturing | 1996 |
| J R Hardisty Developments Ltd | Construction | 2026 |
| J&J Laundry Services Limited | Other services | 2026 |
| J.M. Bell & SON (Bagby) Ltd | Transport & logistics | 2018 |
| JA Birkbeck Limited | Agriculture & fishing | 2024 |
| JAA Projects Ltd | Manufacturing | 2025 |
| JAB Agricultural Contractors Limited | Construction | 2019 |
| Jack and Jills Nursery Schools Ltd | Administrative & support | 2005 |
| Jackson Plant Limited | Construction | 2007 |
| Jacobs & Dalton Limited | Extraterritorial | 2022 |
| Jaipur Restaurant Thirsk Ltd | Hospitality | 2024 |
| Jamlets Properties Ltd | Real estate | 2024 |
| JB Energy Limited | Professional & scientific | 2015 |
| JC Sports Academy Ltd | Education | 2012 |
| Jcracing Ltd. | Wholesale & retail | 2005 |
| JDL Design Limited | Professional & scientific | 1992 |
| Jenny Properties Limited | Real estate | 2016 |
| JH Wind Tech Ltd | Professional & scientific | 2022 |
| JM & HA Property Ltd | Real estate | 2025 |
| JM Chef Solutions Ltd | Hospitality | 2025 |
| JOE Photo Photography Limited | Professional & scientific | 2020 |
| Jogger Limited | Professional & scientific | 2013 |
| John Barber Nutrition Limited | Professional & scientific | 2012 |
| John Brown 4X4 Limited | Wholesale & retail | 2011 |
| John Burgess Services Ltd | Agriculture & fishing | 2006 |
| John Fishwick Limited | Manufacturing | 2013 |
| John M Walker(Farm Buildings) Ltd | Manufacturing | 2003 |
| Johnsons of Thirsk Catering Limited | Hospitality | 2014 |
| Jolly PUB Group Ltd | Hospitality | 2021 |
| Jones Venture Group Ltd | Hospitality | 2025 |
| Joseph Turner Limited | Wholesale & retail | 1997 |
| Journey Homes Limited | Real estate | 2015 |
| Jparker Management Ltd | Information & communication | 2023 |
| Jsjt Limited | Wholesale & retail | 2024 |
| JT Business Development Services Limited | Wholesale & retail | 2021 |
| Juno Recycling Limited | Water & waste | 2023 |
| Justworks Systems Limited | Information & communication | 2014 |
| J’S Timber Limited | Wholesale & retail | 2023 |
| K Dawson Engineering Solutions Limited | Professional & scientific | 2017 |
| K9 Protector Ltd | Administrative & support | 2014 |
| Kaben Developments Limited | Construction | 2015 |
| Kaben Investments Ltd | Construction | 2019 |
| Kaben Properties Limited | Real estate | 2021 |
| Kanoda Holdings Ltd | Financial services | 2018 |
| Kaye Bros Ltd | Real estate | 2025 |
| KC Conveniences Limited | Other services | 2017 |
| KC Hire & Events Limited | Water & waste | 2026 |
| KC Hire Group Ltd | Administrative & support | 2004 |
| KDW Architecture Ltd | Professional & scientific | 2019 |
| Kepwick Estate Limited | Administrative & support | 2011 |
| Kepwick Farms Limited | Real estate | 2011 |
| Kepwick Hotels Limited | Hospitality | 2011 |
| Kevin Ryan Racing Limited | Arts & recreation | 2000 |
| Kevin Walker on Site Plant Services Limited | Manufacturing | 2009 |
| KGF Agriculture & Aggregates LLP | | 2023 |
| Kirkby Fleetham District Angling Club Limited | Arts & recreation | 2004 |
| Kist Accommodates Ltd | Hospitality | 2023 |
| Kist Properties Ltd | Real estate | 2019 |
| Kitchen Shack Limited | Wholesale & retail | 2015 |
| Kitwill Limited | Financial services | 2014 |
| KJ & AC Holdings Ltd | Construction | 2026 |
| KLF Consulting Ltd | Real estate | 2020 |
| KNE Limited | Energy | 2016 |
| Knight's Classics Vintage Car Hire, North Yorkshire Ltd | Administrative & support | 2024 |
| Kodiak Self Storage Limited | Administrative & support | 2024 |
| Kurt's Mobile Caravan Services Ltd | Other services | 2013 |
| L a Wilkinson Limited | Administrative & support | 2002 |
| LAB Properties Northern Ltd | Real estate | 2019 |
| Landimac Trading Ltd | Wholesale & retail | 2024 |
| Langham Real Estate Limited | Real estate | 2022 |