| JDM Sports Cars (UK) Ltd. | Wholesale & retail | 2021 |
| JDT Roofing Services Ltd | Construction | 2025 |
| JE & R Limited | Transport & logistics | 2013 |
| Jeevaratnam TM Ltd | Construction | 2023 |
| Jefferson Property Investments Ltd | Households | 2025 |
| Jeffery & Kokina Properties Ltd | Real estate | 2020 |
| Jeffery Engineering, Management and Consulting Ltd | Professional & scientific | 2016 |
| Jenga Real Estate Limited | Real estate | 2018 |
| Jenna Solution Ltd | Health & social care | 2023 |
| Jenviro Ltd | Professional & scientific | 2020 |
| Jepco (Glebe) Limited | Agriculture & fishing | 2018 |
| Jepco (Marketing) Limited | Wholesale & retail | 2004 |
| Jepco Holdings Limited | Financial services | 2021 |
| Jepco Limited | Financial services | 1997 |
| Jesse's Property Management Limited | Real estate | 2009 |
| Jessica John Property Limited | Real estate | 2025 |
| Jessica Mort Ltd | Professional & scientific | 2021 |
| JG Carpentry (Spalding) Limited | Manufacturing | 2022 |
| JG Multiserv Ltd | Professional & scientific | 2022 |
| JGC & Sons Ltd | Construction | 2025 |
| JGR Contractors 1 Ltd | Construction | 2016 |
| JH Auctions Ltd | Wholesale & retail | 2023 |
| JH Fast Food Ltd | Hospitality | 2025 |
| JH25 Limited | Wholesale & retail | 2025 |
| Jigthings Limited | Administrative & support | 1997 |
| Jimmi's Eats Ltd | Hospitality | 2025 |
| Jit-Pak Limited | Manufacturing | 2002 |
| Jiya & Co Properties Ltd | Construction | 2025 |
| JJ Dent Ltd | Transport & logistics | 2016 |
| JJ Gardenglow Ltd | Administrative & support | 2025 |
| Jjas Plumbing & Heating Limited | Construction | 2024 |
| JJK Building Group Limited | Construction | 2020 |
| JJK Building Limited | Construction | 2015 |
| JJK Building Solutions Limited | Construction | 2020 |
| Jjkins Limited | Real estate | 2022 |
| JJW Agri Ltd | Other services | 2013 |
| Jkuma Trans Ltd | Transport & logistics | 2018 |
| JLR (Sleaford) Limited | Hospitality | 2024 |
| JLR Homes Limited | Real estate | 2022 |
| JLS Home Care and Property Maintenance Ltd | Construction | 2020 |
| JLS Ovens and Furnaces Limited | Manufacturing | 2009 |
| JLS Ovens Spares and Repairs Ltd | Extraterritorial | 2023 |
| JM Drivers Ltd | Transport & logistics | 2016 |
| JMB Holdings (Lincs) Limited | Administrative & support | 2010 |
| JMB Leisure (Skegness) Limited | Hospitality | 2012 |
| JMG OIL Boiler Services Limited | Administrative & support | 2007 |
| Jmk.Transport Ltd | Transport & logistics | 2024 |
| JMS (Holbeach) Limited | Other services | 2004 |
| Jmurawski Ltd | Transport & logistics | 2021 |
| Joblejd Ltd | Transport & logistics | 2015 |
| Jobler Ltd | Manufacturing | 2011 |
| Joemis Investments Limited | Extraterritorial | 2026 |
| Joes Tree Care Ltd | Administrative & support | 2022 |
| John & Alex Transport Ltd | Transport & logistics | 2013 |
| John Halifax & Sons Limited | Transport & logistics | 2003 |
| John Ingle Ltd | Information & communication | 2015 |
| John King and Sons Limited | Extraterritorial | 1997 |
| John Smith Property Maintenance Ltd | Administrative & support | 2009 |
| John Smith Transport Ltd | Transport & logistics | 2020 |
| Johns Roofing Services Ltd | Construction | 2024 |
| Johnson Bros (Fakenham) Limited | Wholesale & retail | 1939 |
| Johnson Financial Ltd | Professional & scientific | 2022 |
| Johnson UK Properties Ltd | Households | 2016 |
| Johnstontek Limited | Wholesale & retail | 2010 |
| Jolanta's Gold Ltd | Wholesale & retail | 2022 |
| Jolly Moulton Ltd | Hospitality | 2024 |
| Jomon's Care Solutions Ltd | Administrative & support | 2022 |
| JON Sealey Sound Engineering Limited | Arts & recreation | 2017 |
| Jonas Jones Ltd | Wholesale & retail | 2022 |
| Jonasstro Limited | Transport & logistics | 2021 |
| Jonathan Ralling Limited | Agriculture & fishing | 2019 |
| Jones Metal Interest Ltd | Wholesale & retail | 2024 |
| Jones Metal Recycling Ltd | Construction | 2024 |
| Jones Roofing Ltd | Construction | 2025 |
| Joossh Ltd | Information & communication | 2014 |
| Jordan Keeble Builders Limited | Construction | 2024 |
| Jordan Kirk Plumbing & Heating Ltd | Construction | 2022 |
| Jordan Kirk Property Limited | Real estate | 2024 |
| Jorge Retail Ltd | Wholesale & retail | 2025 |
| Josbam Ventures Ltd | Administrative & support | 2025 |
| Josebuktoy Medicare Ltd | Health & social care | 2013 |
| Josh Harrison Ltd | Real estate | 2022 |
| Jovi Refurbishments Ltd | Construction | 2025 |
| JP Brickwork Ltd | Construction | 2018 |
| JP Event Hire Ltd | Hospitality | 2025 |
| JP Properties (Spalding) Ltd | Real estate | 2024 |
| JP1 Holding Limited | Financial services | 2023 |
| JPC Paving & Landscaping Services Ltd | Administrative & support | 2026 |
| JPD (Lincs) Ltd | Construction | 2019 |
| Jpmt Consulting Limited | Professional & scientific | 2020 |
| JPS Building Contractors Ltd | Construction | 2022 |
| JR Housing Ltd | Real estate | 2014 |
| JR Primary Transport Ltd | Transport & logistics | 2020 |
| JRI Holdings Limited | Financial services | 2018 |
| JRJ Engineering (Lincs) Ltd | Professional & scientific | 2025 |
| JRL Trans Ltd | Transport & logistics | 2024 |
| JRM Media Ltd | Information & communication | 2025 |
| JRT Commercial Ltd | Manufacturing | 2026 |
| JSB Painter & Decorator Limited | Construction | 2025 |
| Jsmazurek Ltd | Hospitality | 2024 |