| JJ Kelsall Properties Limited | Real estate | 2025 |
| JJ Support Limited | Wholesale & retail | 2011 |
| Jjam Properties Ltd | Hospitality | 2014 |
| JJT Group Ltd | Manufacturing | 2026 |
| JJW Contracts Ltd | Professional & scientific | 2012 |
| JKS Medical Services Wrecsam Ltd | Education | 2026 |
| JL Assessment and Skills Ltd | Education | 2026 |
| Jldp Ltd | Professional & scientific | 2026 |
| JLH Construction Ltd | Construction | 2023 |
| JLM Accommodations Ltd | Households | 2025 |
| JMC Groundworks Limited | Construction | 2016 |
| JME Holdings Ltd | Administrative & support | 2025 |
| JMJ Motors Ltd | Wholesale & retail | 2024 |
| JMR Joinery Limited | Construction | 2008 |
| JMR Properties (North West) Limited | Real estate | 2019 |
| JNJ Trading Limited | Wholesale & retail | 2010 |
| JNP Group Limited | Construction | 2020 |
| Jobart Limited | Professional & scientific | 1990 |
| Joe's Motors Ltd | Wholesale & retail | 2024 |
| John Antony Consultancy Limited | Professional & scientific | 2025 |
| John Dennis Services Ltd | Professional & scientific | 2017 |
| John Horton Cars Limited | Wholesale & retail | 2006 |
| John Kitchen Medical Ltd | Health & social care | 2025 |
| John Peers Limited | Financial services | 2002 |
| John Thomas and Sons Roofing Limited | Construction | 1999 |
| John.R.Hickman Ltd | Construction | 2007 |
| Johnny's Garage Ltd | Wholesale & retail | 2020 |
| Johns Manville Limited | Administrative & support | 1939 |
| Johnstown Barbers Ltd | Other services | 2026 |
| Johnstown Limited | Real estate | 2009 |
| Johnstown Property Limited | Real estate | 2021 |
| Jomar Properties Inc Limited | Real estate | 2012 |
| Jones & Mills Property Ltd | Households | 2024 |
| Jones Bros Constructions Limited | Construction | 2023 |
| Jones Brothers Wholesale Ltd | Wholesale & retail | 2025 |
| Jones Electrics Limited | Construction | 2005 |
| Jones Homes Wrexham Limited | Real estate | 2026 |
| Jones Plumbing and Heating Limited | Construction | 2024 |
| Jones Technology Ltd | Information & communication | 2024 |
| Jordan Contracts (Midlands) Limited | Manufacturing | 2010 |
| Journeycloud Limited | Information & communication | 2017 |
| JP Corporate Limited | Information & communication | 2010 |
| JP Developments (Marford) Limited | Construction | 2014 |
| JP Engraving Limited | Administrative & support | 2009 |
| JPO Property Holdings Ltd | Real estate | 2026 |
| Jprrentals Limited | Real estate | 2025 |
| JPS Grounds Maintenance Limited | Administrative & support | 2021 |
| JPT Construction Holdings Limited | Financial services | 2023 |
| JPT Construction Limited | Construction | 2014 |
| JR Electrical Testing Ltd | Construction | 2026 |
| JR Land and Property Ltd | Households | 2022 |
| JR Roberts Plant Hire Limited | Construction | 2006 |
| JRJ Property Holdings Limited | Real estate | 2019 |
| JS Electrical and Security Services Ltd | Construction | 2025 |
| Jsilverwood Hair Ltd | Other services | 2022 |
| JSR Land and Property Ltd | Real estate | 2024 |
| JTC + Co. Ltd | Arts & recreation | 2026 |
| JTR Group Holdings Limited | Financial services | 2026 |
| JTR Sales Ltd | Wholesale & retail | 2023 |
| Jtrs Property Holdings Limited | Real estate | 2026 |
| Jubilee Beau Unicorn Equine Project CIC | Health & social care | 2021 |
| Jubilee Farm Wellness CIC | Other services | 2025 |
| Junonia Limited | Professional & scientific | 1992 |
| Just Fried Ltd | Hospitality | 2024 |
| Just MOT Wrexham Ltd | Wholesale & retail | 2022 |
| Justseed Limited | Wholesale & retail | 2012 |
| JW Digital Solutions Ltd | Information & communication | 2017 |
| Jwelectricalexperts Ltd | Construction | 2024 |
| Jwilliscroft Limited | Public administration | 2024 |
| Jwmc Ltd | Manufacturing | 2025 |
| JX7 Limited | Hospitality | 2017 |
| K & J Wrexham Foods Limited | Hospitality | 2026 |
| K Curley Construction Services Limited | Construction | 2014 |
| K G Coating Limited | Manufacturing | 1994 |
| K L Financial Limited | Professional & scientific | 2004 |
| K Megamart Ltd | Wholesale & retail | 2025 |
| K R & C Hill & SON Limited | Wholesale & retail | 2005 |
| K&K Elite Homes Ltd | Real estate | 2019 |
| K&M Motorworks Ltd | Wholesale & retail | 2025 |
| K&R Pets Limited | Manufacturing | 2024 |
| K.D.Insulation Services Ltd. | Construction | 2015 |
| K.G.Engineering Services Limited | | 1988 |
| K.R.B Utilities Ltd | Construction | 2026 |
| K.Survey Ltd | Professional & scientific | 2007 |
| K2 Ceramic Studio Limited | Extraterritorial | 2015 |
| K3 Metrology Ltd | Manufacturing | 2025 |
| K3A Homes Ltd | Health & social care | 2025 |
| K9 Paws and Tails Pet-Stay Limited | Other services | 2020 |
| Kaat Media Ltd | Information & communication | 2014 |
| Kairos Support CIC | Health & social care | 2020 |
| Kall Kwik Limited | Professional & scientific | 2011 |
| Kamila Hair and Beauty Limited | Other services | 2024 |
| Kamila Hair Studio Limited | Other services | 2016 |
| Kanimals Ltd | Professional & scientific | 2018 |
| Kansagra Medical Ltd | Health & social care | 2023 |
| Kapeeko Ltd | Wholesale & retail | 2021 |
| Karat Group Ltd | Wholesale & retail | 2018 |
| Karen Hanmer Limited | Arts & recreation | 2014 |
| Karen Sankey Wellness Ltd | Health & social care | 2021 |
| Karmyga Properties Limited | Real estate | 2025 |