| Jack Turner Joinery Ltd | Construction | 2023 |
| Jack&Dary Trans Ltd | Transport & logistics | 2021 |
| Jacklin Distribution Ltd | Wholesale & retail | 2020 |
| Jacklin Group Ltd | Financial services | 2025 |
| Jackson Management Limited | Professional & scientific | 2024 |
| Jackson Property Services (North Lincolnshire) Limited | Construction | 2026 |
| Jackson Sayles Developments Limited | Construction | 2023 |
| Jackson Stapleton Accountants (Grimsby) Limited | Professional & scientific | 2025 |
| Jackson Stapleton Accountants (Lincoln) Limited | Professional & scientific | 2019 |
| Jackson Stapleton Accountants (Retford) Limited | Professional & scientific | 2024 |
| Jackson Stapleton Accountants (Scunthorpe) Limited | Professional & scientific | 2017 |
| Jackson Stapleton Accounting Group Limited | Financial services | 2023 |
| Jackson-Stapleton Limited | Financial services | 2018 |
| Jadealto Limited | Professional & scientific | 1983 |
| JAE Medical Limited | Health & social care | 2021 |
| Jaff Auto Services Ltd | Wholesale & retail | 2025 |
| Jajja Consulting Services Limited | Health & social care | 2012 |
| Jajja-G Investments Limited | Real estate | 2020 |
| James Armstrong Tattoo Limited | Other services | 2025 |
| James Bebb Ltd | Health & social care | 2010 |
| James Broadbent Plumbing and Heating Limited | Construction | 2017 |
| James Cavill Properties Limited | Construction | 2013 |
| James Jacklin Transport Limited | Transport & logistics | 2017 |
| James Subden Limited | Financial services | 2015 |
| Jamie Hickson Upvc Ltd | Construction | 2019 |
| JAN HGV Service Limited | Wholesale & retail | 2025 |
| Jane Bita Ltd | Transport & logistics | 2025 |
| Jane's Mobile Cleaning Limited | Administrative & support | 2007 |
| Janney M Limited | Wholesale & retail | 2014 |
| Japnoor Logistic Consultancy Limited | Transport & logistics | 2019 |
| Jarman Group Ltd | Information & communication | 2026 |
| Jasmine Home Care Specialist Ltd | Health & social care | 2026 |
| Jasnady Ltd | Manufacturing | 2025 |
| Jason Thorpe Plumbing & Heating Services Ltd | Construction | 2015 |
| Jason Threadgold Memorials Limited | Other services | 2025 |
| Jason Threadgold North Lincs Limited | Real estate | 2014 |
| Jawa Logistics Ltd | Transport & logistics | 2021 |
| Jaxmine Business Ltd | Wholesale & retail | 2026 |
| Jaxmine Company Ltd | Wholesale & retail | 2026 |
| JAY a Services Ltd | Wholesale & retail | 2022 |
| JAY D Property Ltd | Households | 2024 |
| Jaye Properties Ltd | Real estate | 2022 |
| Jayne Burnett LA Danza Limited | Arts & recreation | 2019 |
| Jaytech (Ashby) Limited | Information & communication | 2017 |
| JB Allum Ltd | Construction | 2019 |
| JB Matrix Ltd | Information & communication | 2025 |
| JB Mech FAB Ltd | Professional & scientific | 2022 |
| JB Media Group Ltd | Professional & scientific | 2020 |
| JBS Construction 2021 Ltd | Construction | 2021 |
| JBS Transit Ltd | Transport & logistics | 2025 |
| JBZ & Sons Ltd | Transport & logistics | 2013 |
| JC Developments (2025) Limited | Real estate | 2025 |
| JC Developments (Doncaster) Ltd | Construction | 2019 |
| JC Financial Ltd | Administrative & support | 2026 |
| JC Properties (1990) Limited | Real estate | 2025 |
| JC Rentals (Scunthorpe) Ltd | Real estate | 2022 |
| JCF Engineering Limited | Manufacturing | 2008 |
| JCH Medical Ltd | Health & social care | 2019 |
| Jck's Developments Limited | Real estate | 2022 |
| Jck's Group Ltd | Financial services | 2021 |
| Jck's Services Limited | Construction | 2018 |
| JCM Machinery Limited | Wholesale & retail | 2024 |
| JCR Services (Lincs) Ltd | Agriculture & fishing | 2015 |
| JCW Rope Access Ltd | Professional & scientific | 2025 |
| JD Medical Enterprises Ltd | Health & social care | 2025 |
| Jdatec Solutions Ltd | Information & communication | 2013 |
| JDB Professional Access Limited | Construction | 2024 |
| JDL Rendering Ltd | Construction | 2024 |
| JDW Care Ltd | Health & social care | 2023 |
| Jean DU Consulting Ltd | Professional & scientific | 2025 |
| Jecg Realestate Limited | Real estate | 2021 |
| Jecg Services Ltd | Manufacturing | 2014 |
| Jeevan Healthcare Limited | Administrative & support | 2017 |
| Jehovah Jireh and Sons Ltd | Health & social care | 2019 |
| Jenkins Financial Advisers Limited | Financial services | 2011 |
| Jenkins Psychology Consultancy Limited | Information & communication | 2012 |
| Jennie Brookes Mortgage Consultancy Ltd | Financial services | 2021 |
| Jenny Wren (Public House) Limited | Hospitality | 2018 |
| Jenny's Nails Limited | Other services | 2015 |
| Jenopan Leisure Ltd | Real estate | 2024 |
| Jensens Heating & Plumbing Ltd | Construction | 2021 |
| Jess Cleaning Ltd | Administrative & support | 2025 |
| JET Civils Ltd | Construction | 2023 |
| JET Holdings Group Ltd | Financial services | 2025 |
| JF Legal Limited | Professional & scientific | 2023 |
| JF Takeaway Ltd | Hospitality | 2026 |
| JFS Trading Limited | Other services | 2019 |
| JG Accounting & Consulting Limited | Professional & scientific | 2019 |
| JH Property Rental Services Limited | Real estate | 2023 |
| JH Simpson Plumbing & Heating Limited | Construction | 2019 |
| JHH Global Ltd | Professional & scientific | 2009 |
| JHW Developments Limited | Construction | 2004 |
| Jingye Global Metal Recycling Ltd | Wholesale & retail | 2020 |
| Jingye Green Energy Equipment Ltd | Manufacturing | 2024 |
| Jingye Steel (UK) Holding Ltd | Financial services | 2019 |
| Jiraaf Holdings Ltd | Financial services | 2023 |
| Jj's Fabs Ltd | Wholesale & retail | 2024 |
| Jjam Trading Ltd | Financial services | 2025 |
| JJC FMC Ltd | Administrative & support | 2025 |
| JK Anota Motors (Ealand) Ltd | Administrative & support | 2011 |