| Jett-Wind Ltd | Construction | 2025 |
| Jettec Wastewater & Drainage Ltd | Manufacturing | 2021 |
| JH Studio Grammar Limited | Professional & scientific | 2018 |
| JIB UP Grips Limited | Information & communication | 2021 |
| Jigsaw Designs (UK) Limited | Construction | 2010 |
| Jigsaw Players Theatre Company Ltd | Arts & recreation | 2012 |
| Jill Carenza Equestrian Ltd | Agriculture & fishing | 2003 |
| JIM Carpentry Ltd | Manufacturing | 2019 |
| JIM Moffett Consulting Ltd | Professional & scientific | 2024 |
| Jinney Ring Craft Centre Limited | Wholesale & retail | 2005 |
| Jinney Ring Limited | Agriculture & fishing | 2026 |
| JK Senior Holdings Ltd | Financial services | 2019 |
| JKL Property Midlands Ltd | Real estate | 2024 |
| JLC (Worcestershire) Limited | Construction | 2026 |
| JLC Care Ltd | Health & social care | 2018 |
| Jlib Ltd | Information & communication | 2023 |
| Jlkare and Support Limited | Health & social care | 2016 |
| JLN Bromsgrove Limited | Health & social care | 2012 |
| JLN Residential Ltd | Real estate | 2026 |
| JLR Construction & Development Ltd | Construction | 2019 |
| JLR Parts (UK) Limited | Wholesale & retail | 2015 |
| JM Moving Pictures Limited | Information & communication | 2012 |
| JM Shutters Ltd | Construction | 2026 |
| Jmbj Holdings Ltd | Professional & scientific | 2004 |
| JMS Contracting Ltd | Construction | 2026 |
| JNB Freeholds Ltd | Real estate | 2026 |
| JNB Holdings Ltd | Financial services | 2024 |
| JNB Investments Ltd | Real estate | 2024 |
| JNC Camping Ltd | Wholesale & retail | 2019 |
| JNM Logistic Services Ltd | Information & communication | 2012 |
| Joel Hill Enterprises Ltd | Wholesale & retail | 2026 |
| Joey Frost Limited | Administrative & support | 2019 |
| John Bradley Associates Limited | Professional & scientific | 2008 |
| John Evans Farmers Limited | Agriculture & fishing | 1972 |
| John George Limited | Administrative & support | 2001 |
| John Griffiths Consulting Limited | Real estate | 2013 |
| John Keatley (Metals) Limited | Wholesale & retail | 1950 |
| John Sheasby Heating & Plumbing Ltd | Construction | 2012 |
| Joined UP Thinking Limited | Other services | 2025 |
| Joint Payroll Solutions Ltd | Administrative & support | 2025 |
| Jonathan Sproule & Sons Ltd | Construction | 2003 |
| Jordan Williams Upholstery Limited | Wholesale & retail | 2022 |
| Joseph Smith Limited | Administrative & support | 2005 |
| Josephine Solutions Limited | Administrative & support | 2025 |
| JPB Electrical Services Limited | Construction | 2016 |
| JPC Electrical Contractors Ltd | Construction | 2016 |
| Jpcgoodbydevelopments Limited | Information & communication | 2013 |
| Jpmr Retail Ltd | Wholesale & retail | 2024 |
| JPR Automotive Limited | Wholesale & retail | 2025 |
| JPR Logistics (Shropshire) Ltd | Transport & logistics | 2023 |
| Jraa Investments Ltd | Financial services | 2023 |
| JRB Properties Limited | Real estate | 1970 |
| JRC Developers Limited | Construction | 2023 |
| JRC Plant Hire Limited | Construction | 2024 |
| JRD Property Rentals Limited | Real estate | 2024 |
| JS Esell Ltd | Wholesale & retail | 2022 |
| JS Mechanical Building Services Ltd | Energy | 2020 |
| JS Talent Recruitment Specialists Limited | Administrative & support | 2021 |
| JSD Design & Build Ltd | Construction | 2025 |
| Jsexports Ltd | Wholesale & retail | 2025 |
| Jstaholic Limited | Financial services | 2020 |
| Jstv Limited | Information & communication | 2006 |
| Jstx Limited | Real estate | 2026 |
| JT Homes Holding Ltd | Real estate | 2025 |
| JT Homes Midlands Limited | Real estate | 2023 |
| JT Prestige Ltd | Wholesale & retail | 2024 |
| JTB Enterprises Ltd | Wholesale & retail | 2025 |
| Jtelec-Uk Ltd | Construction | 2021 |
| Ju&Charpub Ltd | Hospitality | 2019 |
| Judd Medical Ltd | Wholesale & retail | 1997 |
| Juicy Pubs Limited | Hospitality | 2023 |
| Julia Ford Limited | Arts & recreation | 2025 |
| Junction 5 Commercials Limited | Wholesale & retail | 2025 |
| Just Sold My Land Ltd | Real estate | 2026 |
| Justice Networks Ltd | Professional & scientific | 2018 |
| Jutsons Ltd | Wholesale & retail | 2023 |
| JVI Electrical Installations Limited | Construction | 2009 |
| JW Neurology Consultant Limited | Health & social care | 2017 |
| K Akushie Management Services Limited | Arts & recreation | 2021 |
| K Club Barber Ltd | Other services | 2025 |
| K L Sky Limited | Hospitality | 2017 |
| K N Smith Limited | Construction | 2011 |
| K P Marsh Plastering & Interiors Ltd | Construction | 2019 |
| K S Shocker Limited | Construction | 2016 |
| K W Medical Ltd | Health & social care | 2015 |
| K&S Properties Solutions Ltd | Real estate | 2023 |
| K. Foster & SON Ltd | Real estate | 2020 |
| K.H Management Ltd | Hospitality | 2024 |
| K1 Professional Limited | Wholesale & retail | 2017 |
| K2 Accounting Solutions Limited | Professional & scientific | 2019 |
| K2 Electrical Solutions Limited | Construction | 2009 |
| Kalbir Consulting Limited | Information & communication | 2015 |
| Kalos Solutions Ltd | Construction | 2025 |
| Kanon Compliance Ltd | Information & communication | 2025 |
| Karma Studios Ltd | Information & communication | 2025 |
| Kart Grand Prix UK Ltd | Administrative & support | 2010 |
| KAS UK Logistics Ltd | Transport & logistics | 2024 |
| Katie Phillips Coaching Ltd | Other services | 2025 |
| Katunda UK Limited | Information & communication | 2022 |
| Kavanagh Group Consultancy Limited | Information & communication | 2026 |