| JP Materials Limited | Wholesale & retail | 2020 |
| JRH Property Investments Limited | Real estate | 2019 |
| JS Galvin (Midlands) Limited | Manufacturing | 2018 |
| JSL Logistics Ltd | Transport & logistics | 2023 |
| JSR Property Asset Management Limited | Real estate | 2026 |
| Jtecomgroup Ltd | Wholesale & retail | 2026 |
| Juiced Electrical Ltd | Construction | 2026 |
| Jungle Juniorz Ltd | Health & social care | 2023 |
| Just a Step UK Ltd | Wholesale & retail | 2018 |
| Just Affords Ltd | Wholesale & retail | 2024 |
| Just Crisps Ltd | Manufacturing | 2010 |
| Just OIL Limited | Manufacturing | 2007 |
| Just Wood Carpentry Ltd | Construction | 2017 |
| JWF Commercial Solutions Limited | Construction | 2013 |
| JWF Group (Midlands) Ltd | Financial services | 2015 |
| Jwf(Building Solutions) Ltd | Construction | 2008 |
| JWL Accountancy Limited | Professional & scientific | 2021 |
| JWL Estate Planning Ltd | Professional & scientific | 2021 |
| JYG Consulting Ltd | Public administration | 2025 |
| Jzlighting Ltd | Professional & scientific | 2019 |
| K E Harding's Consultancy Ltd | Professional & scientific | 2019 |
| K E Hollis Limited | Construction | 2003 |
| K J Coffee Solutions Limited | Manufacturing | 2022 |
| K S Knight Motor Engineers Limited | Manufacturing | 2014 |
| K Transport Limited | Administrative & support | 2016 |
| K.Fox Enterprises Limited | Administrative & support | 2020 |
| Karar Pizza Ltd | Hospitality | 2025 |
| Karl Grace Design Limited | Professional & scientific | 2007 |
| Kate Casali Ltd | Professional & scientific | 2024 |
| KBR Automation Limited | Information & communication | 2010 |
| KDI Electrical Ltd | Administrative & support | 2025 |
| Keepers Garden Rooms Ltd | Construction | 2022 |
| KEL Consult Ltd | Professional & scientific | 2026 |
| Kelly Tolan Coaching and Consultancy Practice Ltd | Professional & scientific | 2024 |
| Kenda GB Rugeley Limited | Wholesale & retail | 1988 |
| Kentrome Freehold Limited | Administrative & support | 2017 |
| Kettle Roofing Ltd | Construction | 2024 |
| Key Prep Groundworks Ltd | Construction | 2019 |
| Kifinas Commercial Estates Limited | Real estate | 2019 |
| Kifinas Estates Limited | Real estate | 2018 |
| KILLER5 Ltd | Professional & scientific | 2010 |
| Kind Hearts Care & Support Limited | Health & social care | 2013 |
| Kingscroft Construction Holdings Ltd | Real estate | 2016 |
| Kingscroft Construction Ltd | Construction | 2005 |
| Kingsland Road Management Limited | Households | 1992 |
| Kingsley Media Ltd | Information & communication | 2016 |
| KLR Social Work Limited | Health & social care | 2015 |
| KM Group Enterprise Limited | Financial services | 2020 |
| KN1GHT Solutions Limited | Information & communication | 2016 |
| Knight Live Limited | Administrative & support | 2024 |
| Kostas Premium Foods Limited | Wholesale & retail | 2025 |
| KPL Electrical Contractors Ltd | Construction | 2018 |
| KSW Haulage Ltd | Transport & logistics | 2025 |
| Kube Contract Management Limited | Professional & scientific | 2018 |
| Kubu Holdings Limited | Financial services | 2025 |
| Kubu Smart Home Limited | Information & communication | 2025 |
| Kubu Smart Limited | Manufacturing | 2019 |
| Kuga Properties Ltd | Real estate | 2011 |
| L & C Motors Limited | Wholesale & retail | 2002 |
| L J B Surveying Limited | Professional & scientific | 2022 |
| L W Recycling Ltd | Water & waste | 2009 |
| L&J Ironing Ltd | Other services | 2025 |
| L.Hartshorne Ltd | Professional & scientific | 2025 |
| Lagan Consultancy Limited | Professional & scientific | 2018 |
| Laings Foundry (Edinburgh) Limited | Manufacturing | 2012 |
| Lakeshaw Homes Ltd | Construction | 2025 |
| Langley Pave, Resin & TAR Ltd | Construction | 2025 |
| Larch 68 Limited | Extraterritorial | 2013 |
| Larp Consulting Ltd | Information & communication | 2025 |
| Laser Services Limited | Manufacturing | 2008 |
| Lashman Estates Limited | Real estate | 2011 |
| Laszlo's Lettings Limited | Real estate | 2026 |
| Lay`S Wholesale Meats Limited | Wholesale & retail | 2002 |
| Lazy Hill Management Company Limited | Households | 2014 |
| LCI Construction Services Limited | Construction | 2018 |
| LCI Contracting Ltd | Construction | 2019 |
| LCI Rail Group Limited | Construction | 2015 |
| LCI Rail National Projects Ltd | Water & waste | 2016 |
| LCJ Tamworth Ltd | Arts & recreation | 2021 |
| Leap 7 Ltd | Information & communication | 2018 |
| Leedham Property Services (Midlands) Ltd | Construction | 2020 |
| Level Crossing Installations Limited | Construction | 2010 |
| Level II Ltd | Construction | 2005 |
| Leyland Brands Ltd | Wholesale & retail | 2021 |
| Liberty Brewing Limited | Financial services | 2013 |
| Liberty Maple Inc Ltd | Manufacturing | 2021 |
| Libra Properties Limited | Construction | 2003 |
| Lichfield Automation Solutions Limited | Professional & scientific | 2024 |
| Lichfield Caravans Limited | Wholesale & retail | 1990 |
| Lichfield Eats Ltd | Hospitality | 2023 |
| Lichfield Home Care Ltd | Health & social care | 2025 |
| Lichfield Plastics Limited | Manufacturing | 1975 |
| Lichfield Printers Ltd | Manufacturing | 2003 |
| Lichfield Remapping Solutions Limited | Wholesale & retail | 2022 |
| Lift Source (UK) Limited | Manufacturing | 1991 |
| Linfinity Consulting Ltd | Hospitality | 2022 |
| Linh Long Limited | Hospitality | 2025 |
| Link Support Limited | Professional & scientific | 2017 |
| Lipoedema Hub CIC | Information & communication | 2025 |
| Litter ME Removals Ltd | Water & waste | 2026 |