| Ignite Technologies Limited | Information & communication | 2012 |
| Ijah Trading Ltd | Wholesale & retail | 2025 |
| Immersive Faith 360 Ltd | Education | 2019 |
| Impact Search Ltd | Administrative & support | 2019 |
| Include ME & Unmute Ltd | Information & communication | 2022 |
| Income Tax Returns Limited | Extraterritorial | 2019 |
| Independence Hub Ltd | Health & social care | 2026 |
| Industrial and Commercial Heating (Central Services) Ltd | Extraterritorial | 1993 |
| Industrial Concrete Tanks Limited | Construction | 2015 |
| Industrial Process Control Limited | Professional & scientific | 2003 |
| Infinity Piping Engineering Ltd | Professional & scientific | 2026 |
| Infinity Taxi Rentals Ltd | Transport & logistics | 2026 |
| INK Splash Ltd | Manufacturing | 2019 |
| Inman INK Ltd | Information & communication | 2015 |
| Inner Rise Ltd | Professional & scientific | 2025 |
| INOV8 Construction Limited | Construction | 2023 |
| INOV8 Projects Ltd | Construction | 2023 |
| Inspire to Move Forward Ltd | Health & social care | 2018 |
| Intelligent Carbon Solutions Ltd | Professional & scientific | 2020 |
| Inter Yorks Limited | Transport & logistics | 2025 |
| INVESTCO24 Ltd | Manufacturing | 2025 |
| Investible Properties Ltd | Real estate | 2024 |
| Ipfortress Ltd | Information & communication | 2018 |
| IPN Property Services Limited | Construction | 2018 |
| Ipso Print Limited | Manufacturing | 1969 |
| IR & R Limited | Wholesale & retail | 2024 |
| Iron Temple Gym Ltd | Arts & recreation | 2026 |
| Irvinghirst Ltd | Wholesale & retail | 2024 |
| Issh Group Limited | Financial services | 2015 |
| IST Resourcing Ltd | Administrative & support | 2023 |
| IT BOT Ltd | Information & communication | 2025 |
| IT Testworks Limited | Information & communication | 2025 |
| Italexperience Ltd | Hospitality | 2017 |
| Itechno Limited | Other services | 2016 |
| J & B Food & Drink Ltd | Hospitality | 2023 |
| J & D Properties (Leeds) Ltd | Real estate | 2025 |
| J & S Hotel Enterprise Limited | Hospitality | 2003 |
| J & S Venture Limited | Hospitality | 2005 |
| J B Engraving Ltd | Wholesale & retail | 2025 |
| J Capital Holdings Limited | Extraterritorial | 2025 |
| J Miles Storage Limited | Transport & logistics | 2024 |
| J Murphy Aggs Ltd | Water & waste | 2018 |
| J Murphy Truck & Plant Limited | Water & waste | 2001 |
| J V Recruit Ltd | Administrative & support | 2018 |
| J&S Food Enterprises Ltd | Hospitality | 2025 |
| J. R. Whyte Limited | Administrative & support | 1997 |
| JA Pizza's Ltd | Hospitality | 2021 |
| Jamard Limited | Hospitality | 2010 |
| Jambo Linguists Limited | Professional & scientific | 2023 |
| James Michael Smith Limited | Extraterritorial | 2024 |
| Jampot and Sunday Limited | Manufacturing | 2013 |
| Jane Fenwick & Associates Ltd | Professional & scientific | 2015 |
| JAS Psychology Ltd | Education | 2024 |
| Jaspers Building Services Limited | Construction | 2022 |
| Jawanda Consultancy Limited | Information & communication | 2024 |
| Jawanda Investments Limited | Real estate | 2024 |
| Jawanda Property Investments Limited | Real estate | 2026 |
| Jawanda Trading Limited | Administrative & support | 2024 |
| Jayne E Verity Limited | Other services | 2003 |
| JB Collective Ltd | Professional & scientific | 2026 |
| JB Electrical & Controls Ltd | Manufacturing | 2026 |
| JB Leeds Limited | Hospitality | 2016 |
| JB Property Leeds Ltd | Construction | 2026 |
| JD Strategic Consultancy Ltd | Professional & scientific | 2025 |
| JDM Business Services Ltd | Professional & scientific | 2017 |
| Jdnetworks Limited | Administrative & support | 2003 |
| Jenny Scott Send Consultancy Services Ltd | Education | 2023 |
| Jess Williams Creative Ltd | Arts & recreation | 2023 |
| JEV Energy Ltd | Real estate | 2024 |
| Jewel Care Limited | Administrative & support | 2022 |
| JH Yorkshire Ltd | Construction | 2025 |
| Jhnb Ltd | Professional & scientific | 2020 |
| Jigsaw Gyms Limited | Arts & recreation | 2009 |
| Jipc Limited | Information & communication | 2022 |
| JK Bros Investments Ltd | Households | 2024 |
| JKD Emporium Ltd | Wholesale & retail | 2026 |
| JLC Decorators Ltd | Construction | 2026 |
| JLM Energy Ltd | Construction | 2024 |
| JLM Finance Ltd | Financial services | 2024 |
| JLW Property Solutions Ltd | Real estate | 2025 |
| JM Elevator Solutions Ltd | Professional & scientific | 2025 |
| JMP Design Limited | Professional & scientific | 2007 |
| JMS Electrical Contractors Ltd | Construction | 2023 |
| JNK Property Rentals Ltd | Real estate | 2025 |
| Jobling Transport Services Ltd | Transport & logistics | 2014 |
| Jodlproductions Ltd | Manufacturing | 2026 |
| Joes AI Ltd | Administrative & support | 2024 |
| Johal Developments Limited | Real estate | 2007 |
| Johal Group Ltd | Real estate | 2022 |
| Johal Group Services Limited | Construction | 2019 |
| John Little Construction 1 Ltd | Construction | 2017 |
| Jonathan Muir Construction Limited | Construction | 2019 |
| Jonathan Wormald Associates Limited | Professional & scientific | 2005 |
| Jones Maintenance York Limited | Construction | 2022 |
| Joule Media Limited | Information & communication | 2021 |
| Joyce Investments Limited | Financial services | 2026 |
| JPM Brickwork Ltd | Construction | 2021 |
| JRL Accountancy Ltd | Professional & scientific | 2024 |
| JRW Rental Ltd | Real estate | 2022 |
| JS Deliveries Ltd | Transport & logistics | 2025 |