| Hota Northallerton Limited | Hospitality | 2024 |
| House Clickers Limited | Real estate | 2017 |
| Howie Property Ltd | Construction | 2015 |
| Howlett Associates Limited | Administrative & support | 2023 |
| HRT Building Solutions Limited | Construction | 2016 |
| Hs-Silver Ltd | Manufacturing | 2011 |
| HT Energy Limited | Construction | 1999 |
| Hudson Moore Partners Limited | Administrative & support | 2024 |
| Hungry Jacks Hospitality Limited | Hospitality | 2001 |
| Hutchinson Hobbs Limited | Wholesale & retail | 2014 |
| Hydroblast (U.K) Limited | Professional & scientific | 2017 |
| Hydroblast Cleaning Limited | Professional & scientific | 2017 |
| Hydroblast Cleaning Services Limited | Professional & scientific | 2017 |
| Hydroblast Cleaning Solutions Limited | Professional & scientific | 2017 |
| Hydroblast Group Limited | Extraterritorial | 2019 |
| Hydroblast Industrial Jetting Ltd | Professional & scientific | 2017 |
| Hydroblast Technologies Ltd | Extraterritorial | 2019 |
| Hydroblast UK Rentals Limited | Extraterritorial | 2019 |
| Hydroblasting Ltd | Professional & scientific | 2017 |
| Hydroblasting Rentals Ltd | Extraterritorial | 2019 |
| Hydroblasting Training Ltd | Extraterritorial | 2019 |
| I C Polytunnels Limited | Construction | 2016 |
| I D T Trading Ltd | Wholesale & retail | 2016 |
| IAN Calder Production Services Limited | Arts & recreation | 2008 |
| ICH Dien Solutions Limited | Professional & scientific | 2023 |
| Iggy the VET Ltd | Extraterritorial | 2017 |
| Imaginand Limited | Information & communication | 2025 |
| Imedia Enterprises Limited | Hospitality | 2019 |
| Immuquest Limited | Health & social care | 2002 |
| Impact Engineering Services and Consultancy Limited | Professional & scientific | 2024 |
| Imperial Blue Funding 1 Limited | Financial services | 2015 |
| Imprint Business Services Limited | Manufacturing | 2003 |
| Indigo 3 Consulting Ltd | Professional & scientific | 2013 |
| Industrial Workwear Limited | Manufacturing | 1999 |
| INHAUS3 Limited | Wholesale & retail | 2019 |
| Inveree Limited | Hospitality | 2020 |
| Invincible Mindset Coaching Ltd | Health & social care | 2023 |
| Ipco Management Services Limited | Professional & scientific | 2000 |
| Ironing Crew Limited | Administrative & support | 2023 |
| IVY Cottages 1964 Limited | Extraterritorial | 2014 |
| IVY MAY Properties and Lettings Ltd | Real estate | 2026 |
| IX7 Ltd | Professional & scientific | 2015 |
| J a Sales and Service Limited | Manufacturing | 2012 |
| J Barthram & SON Limited | Other services | 2011 |
| J G Bell Developments Limited | Construction | 2020 |
| J J Leisure (North East) Ltd | Other services | 2020 |
| J O'Connell Plant Hire Limited | Administrative & support | 2002 |
| J Read Consultancy Limited | Professional & scientific | 2024 |
| J W Teward & Sons (Haulage) Ltd | Transport & logistics | 2022 |
| J&M Waldron Livestock Ltd | Agriculture & fishing | 2024 |
| J. H. Medical Services Limited | Health & social care | 2016 |
| J.J.J. Optical Limited | Wholesale & retail | 1998 |
| J.O.M Tearooms Company Ltd | Hospitality | 2024 |
| J.S. Johnson (Haulage) Limited | Transport & logistics | 2010 |
| Jackie KAY Limited | Professional & scientific | 2017 |
| Jalc Northallerton Ltd | Real estate | 2019 |
| James Bourne-Arton Limited | Professional & scientific | 2015 |
| James Greco Limited | Other services | 2005 |
| James H Ward Properties Limited | Real estate | 2007 |
| Jaya's Catering Limited | Hospitality | 2026 |
| Jayden Ethnic Market Limited | Hospitality | 2024 |
| JCF Ropes Ltd | Professional & scientific | 2023 |
| Jd's Hair Limited | Other services | 2018 |
| JDC Electrical Install Ltd | Construction | 2020 |
| Jdjf Limited | Financial services | 2010 |
| Jefferson Fabrications & Engineering Ltd | Manufacturing | 2024 |
| Jevoah Jireh Consultancy Ltd | Health & social care | 2016 |
| JF Weld Services Limited | Manufacturing | 2019 |
| JFW Swiers Farming Company | Agriculture & fishing | 2012 |
| Jg's Hair Limited | Other services | 2018 |
| Jhago Ltd | Real estate | 2020 |
| JHF Farming | Agriculture & fishing | 2010 |
| JHK Biomass Services Ltd | Construction | 2022 |
| JHK Contractors Limited | Manufacturing | 2016 |
| JHK Property North Yorkshire Ltd | Real estate | 2019 |
| JHK Renewable Energy Limited | Energy | 2025 |
| JJ Hugo Ltd | Professional & scientific | 2026 |
| JJ Racing Ltd | Arts & recreation | 2026 |
| Jj&Co Excavation and Landscaping Services Ltd | Administrative & support | 2025 |
| JJH Hospitality Limited | Hospitality | 2024 |
| JJM Electrics Ltd | Construction | 2026 |
| JLE Safety Solutions Ltd | Professional & scientific | 2021 |
| Jm&D Ltd | Health & social care | 2024 |
| JMF Consulting AG LP | | 2024 |
| Jobstopper Limited | Hospitality | 2009 |
| JOE Seels Farming Ltd | Information & communication | 2024 |
| Joebeau Properties Ltd | Real estate | 2026 |
| John Harrison KC Limited | Professional & scientific | 2017 |
| John Prest & Co | Real estate | 2003 |
| John Raper Limited | Real estate | 1973 |
| John Stanley Farriers Limited | Agriculture & fishing | 2009 |
| Jones Gifts Ltd | Wholesale & retail | 2025 |
| Jonesgreen Developments Ltd | Real estate | 2019 |
| Jotika Limited | Manufacturing | 1991 |
| Jo’S Jaunts Ltd | Agriculture & fishing | 2025 |
| JP Site Services Limited | Professional & scientific | 2013 |
| Jpfinco Limited | Financial services | 2011 |
| JR Transport Ltd | Transport & logistics | 2024 |
| JRM33 Holdings Limited | Financial services | 2026 |
| JRM33 Investments Limited | Real estate | 2026 |