| James, ROY and Stephen Limited | Other services | 2016 |
| Jamie Gregory Roofing Ltd | Construction | 2026 |
| Janet Simpson Ltd | Health & social care | 2023 |
| Japan Vacuum Instruments Limited | Wholesale & retail | 2012 |
| Jarrow Components Limited | Wholesale & retail | 2014 |
| Jason R Berrington Consulting Limited | Professional & scientific | 2023 |
| Java Engineering Services Ltd | Manufacturing | 2024 |
| JAX CON Ltd | Construction | 2019 |
| Jaxon's Contractors Limited | Construction | 2018 |
| JAY MC Motors Ltd | Wholesale & retail | 2024 |
| JAY MC Tyres Ltd | Wholesale & retail | 2022 |
| Jaya Birch 63 Ltd | Administrative & support | 2025 |
| Jazz Rumours Limited | Other services | 2017 |
| JBS Joinery (NW) Ltd | Construction | 2022 |
| JBV Group Holdings Limited | Construction | 2002 |
| JBW Marine Ltd | Other services | 2023 |
| JCC Property Ltd | Real estate | 2018 |
| Jclc Property Holdings Limited | Administrative & support | 2015 |
| JCP Offshore Ltd | Manufacturing | 2023 |
| Jcpp Electrical Ltd | Construction | 2019 |
| Jcrp Engineering Ltd | Professional & scientific | 2025 |
| JD Aesthetics Ltd | Health & social care | 2016 |
| JD Aesthetics Training Academy Ltd | Education | 2025 |
| JD Brickwork Limited | Construction | 2021 |
| JD Education Finance Services Limited | Professional & scientific | 2013 |
| JD Estates Management Limited | Real estate | 2021 |
| JDW Conservatories Ltd | Construction | 2025 |
| JDW Windows Ltd | Construction | 2025 |
| Jefferson Civil Engineering Limited | Construction | 2007 |
| Jeffreys Transport Limited | Transport & logistics | 2013 |
| Jelm Investments Limited | Real estate | 2019 |
| JEM Living Ltd | Real estate | 2020 |
| JEM Resourcing Solutions Ltd | Administrative & support | 2022 |
| Jennions Macken Limited | Professional & scientific | 2012 |
| JG Structural Design Ltd | Professional & scientific | 2022 |
| Jgdl Property Limited | Real estate | 2024 |
| JJ Campervan Hire Limited | Administrative & support | 2019 |
| JJ Plumbing & Heating (Widnes) Limited | Construction | 2021 |
| JJK Sports Ltd | Professional & scientific | 2016 |
| JK Pristine Exterior Cleaning Services Limited | Administrative & support | 2026 |
| JK Reinforcement Limited | Construction | 2025 |
| JKG Trans Limited | Transport & logistics | 2017 |
| Jknib Ltd | Administrative & support | 2024 |
| JKU Properties Limited | Real estate | 2020 |
| JL Dean Holdings Limited | Real estate | 2024 |
| JL Engineering & Fabrication Ltd | Professional & scientific | 2018 |
| JL GAS Services Ltd | Construction | 2017 |
| JL PYE Ltd | Real estate | 2021 |
| JLA Property Investment Ltd | Real estate | 2025 |
| JLT Properties and Holdings Limited | Real estate | 2022 |
| JM Safety Training Limited | Education | 2010 |
| JMA Cleaning Services Limited | Administrative & support | 2025 |
| JMD Property and Homes Ltd | Real estate | 2020 |
| JMG Victoria Ltd | Professional & scientific | 2017 |
| JMI Moving Group Ltd | Financial services | 2021 |
| JML Property Holdings Ltd | Real estate | 2022 |
| JMR Engineering Consultants Limited | Professional & scientific | 2006 |
| JMR Inspection Limited | Professional & scientific | 2007 |
| JMR Renewables Ltd | Professional & scientific | 2024 |
| JO Box Counselling Limited | Health & social care | 2024 |
| JO Brittles Limited | Administrative & support | 2023 |
| Johms Electrical Services Ltd | Construction | 2026 |
| John Geddes (Cycles) Limited | Wholesale & retail | 1978 |
| John Laws Welly 26 Limited | Arts & recreation | 2026 |
| John Laws Welly Limited | Arts & recreation | 2019 |
| John Wall Drainage Service Ltd. | Water & waste | 1996 |
| Johnson Design and Installation Ltd | Construction | 2020 |
| Jordan's Aquatics Ltd | Wholesale & retail | 2025 |
| Joseph Tabner 2015 Limited | Administrative & support | 2012 |
| Josh Calland High Performance Ltd | Education | 2024 |
| Jover Group Limited | Administrative & support | 2025 |
| Jover Media Ltd | Information & communication | 2025 |
| Jover Wine Club Ltd | Wholesale & retail | 2025 |
| JP Motor Bodies Limited | Wholesale & retail | 1995 |
| JPL Cabs Ltd | Transport & logistics | 2007 |
| JPN Technologies Ltd | Professional & scientific | 2025 |
| JR Elite Commercials Ltd | Wholesale & retail | 2025 |
| JS Abodes Ltd | Real estate | 2025 |
| JS Electrical NW Ltd | Construction | 2025 |
| JSI Motor Group Ltd | Wholesale & retail | 2026 |
| Jskm Ltd | Wholesale & retail | 2019 |
| Jtcs Logistics Limited | Transport & logistics | 2019 |
| Julia Westland Ltd | Administrative & support | 2025 |
| Julie Roberts Therapy Ltd | Health & social care | 2022 |
| Just BEE YOU (Northwest) Community Interest Company | Health & social care | 2021 |
| JW Properties (Carlisle) Ltd | Real estate | 2023 |
| JWG Property Services Limited | Real estate | 2018 |
| K & S Paving and Groundworks Limited | Construction | 2017 |
| K J G Investments Limited | Professional & scientific | 2003 |
| K R GAS Services Limited | Professional & scientific | 2014 |
| K&L Associates (Scientific & Logistical Support) Ltd | Professional & scientific | 2010 |
| K&M Heritage Holdings Limited | Real estate | 2025 |
| K.B.J. Management Limited | | 1993 |
| K.E.R Maintenance Ltd | Construction | 2022 |
| K.P. Sumner Limited | Other services | 1998 |
| K4 Developments Limited | Real estate | 2003 |
| KAH Happiness Limited | Wholesale & retail | 2025 |
| Kaizen Complete Ltd | Arts & recreation | 2026 |
| Kaizenhancements Ltd | Information & communication | 2022 |
| Kalman Projects Limited | Construction | 2025 |