| JC Quality Construction Ltd | Construction | 2008 |
| JDW Rooflines Limited | Construction | 2016 |
| JEH Services Ltd | Professional & scientific | 2016 |
| Jelan Financial Services Limited | Professional & scientific | 2008 |
| JEN405 Ltd | Financial services | 2021 |
| Jepson's RV Ltd | Hospitality | 2019 |
| Jervis Vending Ltd | Wholesale & retail | 2020 |
| Jessica & Morton Limited | Professional & scientific | 2024 |
| JEV Graphics Limited | Other services | 2018 |
| Jgsgshqg Ltd | Education | 2025 |
| JHS 2012 Limited | Professional & scientific | 2012 |
| JI Holdings Ltd | Real estate | 2023 |
| Jimobi Limited | Real estate | 2017 |
| Jkbooks Ltd | Professional & scientific | 2025 |
| JL Architectural Designs Ltd | Construction | 2020 |
| JL Industries Ltd | Manufacturing | 2016 |
| JLL (HW) Holdings Ltd | Professional & scientific | 2019 |
| JMF Business Services Limited | Professional & scientific | 2014 |
| Jmse Electrical Ltd | Construction | 2015 |
| JNT Business Limited | Professional & scientific | 2026 |
| John Cross Limited | Construction | 2022 |
| John H Jarmany Wealth Limited | Financial services | 2023 |
| John Hall Schoolwear Limited | Manufacturing | 2000 |
| John Long Consultancy Limited | Professional & scientific | 2014 |
| John Mckenna Limited | Construction | 2003 |
| John Pallister Limited | Administrative & support | 2002 |
| John Patterson Fire Protection Systems Ltd | Public administration | 2002 |
| John Robinson and Sons (Plasterers) Limited | Construction | 1948 |
| Johnston Yates Business Solutions Ltd | Information & communication | 2021 |
| Jolly Accountancy Services Limited | Professional & scientific | 2013 |
| Jonway Vehicles Ltd | Wholesale & retail | 2025 |
| Joseph Lanzante Training Limited | Education | 2015 |
| Josh Reilly Civil Engineering Limited | Construction | 2022 |
| Joshua Thornber Limited | Agriculture & fishing | 2024 |
| Joy First Ltd | Professional & scientific | 2015 |
| Joyful Life Limited | Other services | 2022 |
| JP Fleet Services Ltd | Wholesale & retail | 2026 |
| JPA Sports Limited | Wholesale & retail | 2018 |
| JPL North West Ltd | Financial services | 2026 |
| JPW Consulting Services Limited | Professional & scientific | 2016 |
| JRC Racing Ltd | Wholesale & retail | 2017 |
| Jrgl Limited | Administrative & support | 2007 |
| Jtbc Limited | Professional & scientific | 2025 |
| Jtsp Limited | Professional & scientific | 2020 |
| Judith Douglas Town Planning Limited | Professional & scientific | 2015 |
| Just in Glass Ltd | Construction | 2026 |
| Justqms Ltd | Professional & scientific | 2025 |
| JV Commercial Installation Limited | Professional & scientific | 2014 |
| JWR Haulage Limited | Transport & logistics | 2014 |
| K Consultancy (Lancashire) Ltd. | Professional & scientific | 2007 |
| K J Donnelly Limited | Health & social care | 2022 |
| K R Jones Ltd | Health & social care | 2012 |
| K Worthington Design and Build Ltd | Construction | 2014 |
| K&J Sims Group Ltd | Financial services | 2025 |
| K2GRO.COM Limited | Extraterritorial | 2021 |
| Kabeth Properties Ltd | Real estate | 2024 |
| Kaffitar Ltd | Wholesale & retail | 2026 |
| KAI Anstead Marketing Ltd | Professional & scientific | 2026 |
| Kanger Kelly Ltd | Information & communication | 2017 |
| Kapri Holdings Ltd | Real estate | 2022 |
| Kaptured and Co. Ltd | Professional & scientific | 2025 |
| Kate Atkinson Ltd | Other services | 2022 |
| Kate Pollitt Limited | Professional & scientific | 2025 |
| Katie Walsh Travel Limited | Administrative & support | 2015 |
| KAY Tekk Ltd | Other services | 2021 |
| Kay's Caring Services Limited | Health & social care | 2022 |
| Kaya Beauty Therapy and Aesthetics Ltd | Other services | 2015 |
| KCF Asset Finance Ltd | Financial services | 2023 |
| Kebabs and Pizzas Ltd | Hospitality | 2026 |
| Keep Beautiful Salon and Spa Ltd | Other services | 2018 |
| Keep Safe Locks and Door Repairs Ltd | Other services | 2019 |
| Kego Limited | Real estate | 2017 |
| Keith Clement Auto Electrical Service Limited | Wholesale & retail | 2017 |
| Kellie Hughes Limited | Other services | 2002 |
| Kellie Hughes Properties Ltd | Real estate | 2019 |
| Kemple 1972 Limited | Extraterritorial | 2014 |
| KEN Mcneill Limited | Manufacturing | 1976 |
| Ketolife Ltd | Manufacturing | 2012 |
| Key Financial Management Limited | Professional & scientific | 1999 |
| Keystone Finance Limited | Financial services | 2024 |
| KGS Group Ltd | Wholesale & retail | 2009 |
| Khybers Foods Ltd | Hospitality | 2026 |
| KIB Sustainable Energy Limited | Construction | 2012 |
| Kiddiwinks Day Nursery (Blackburn) Limited | Health & social care | 2011 |
| Kiddiwinks Day Nursery Limited | Health & social care | 2003 |
| KIN Salons Limited | Other services | 2015 |
| Kinesin Ltd | Information & communication | 2025 |
| Kingsbrook Consulting Ltd | Professional & scientific | 2018 |
| Kingsley Windows Ltd | Construction | 2022 |
| Kitchen Doors Holdings Ltd | Financial services | 2018 |
| Kitchen Doors NW Limited | Manufacturing | 2000 |
| KLB Recovery Ltd | Other services | 2015 |
| KLB Tracing Services Ltd | Professional & scientific | 2017 |
| Kmchr Holdings Limited | Professional & scientific | 2019 |
| KN Global 2026 Limited | Manufacturing | 2026 |
| Knead & Grind Ltd | Extraterritorial | 2025 |
| Knight Labels Limited | Manufacturing | 2012 |
| Kongo Cruising Limited | Administrative & support | 2025 |
| Kontur Bags Ltd | Manufacturing | 2025 |
| Kopter 22 Ltd | Other services | 2022 |