| K11 Developments Ltd | Construction | 2015 |
| Kads (Design) Ltd | Professional & scientific | 2016 |
| Kahlon Property Ltd | Real estate | 2017 |
| Kandola Limited | Hospitality | 2017 |
| Karmarg Ltd | Transport & logistics | 2021 |
| Kasa Limited | Hospitality | 2020 |
| KB Electrical & Event Services Limited | Construction | 2019 |
| KCH (Birmingham JQ Legge) Ltd | Construction | 2021 |
| KCH (Birmingham JQ) Limited | Construction | 2019 |
| KCH Investment Services Ltd | Real estate | 2020 |
| Keldek Automotive Technical Services Limited | Professional & scientific | 2022 |
| Kennedy Properties (Midlands) Ltd | Real estate | 2019 |
| KF Sports Active Ltd | Education | 2024 |
| KG Dynamics Ltd | Information & communication | 2024 |
| Kindle Enterprises Ltd | Information & communication | 2010 |
| King Street Barbers Ltd | Other services | 2022 |
| Kingdom Logistics UK Ltd | Wholesale & retail | 2016 |
| Kings Crescent Homes Limited | Other services | 2019 |
| Kingsland Butchers Limited | Wholesale & retail | 2018 |
| Kingswood Poultry (2011) Limited | Wholesale & retail | 2012 |
| Kirkland Maintenance Services Limited | Construction | 2013 |
| Kirpa Management Ltd | Real estate | 2026 |
| KJD Jewellers Limited | Extraterritorial | 1940 |
| KJSBARS2 Ltd | Hospitality | 2024 |
| Klean Concept Services Limited | Administrative & support | 2024 |
| KOV Industries Ltd | Wholesale & retail | 2024 |
| KP Lynch Services Ltd | Wholesale & retail | 2026 |
| KPJ Property Development Ltd | Real estate | 2025 |
| Krister Raul Limited | Wholesale & retail | 2024 |
| KT Operators Ltd | Wholesale & retail | 2022 |
| KUC Trans Ltd | Transport & logistics | 2019 |
| L M S Repairs Ltd | Wholesale & retail | 2025 |
| L P S Electrical Ltd | Manufacturing | 1997 |
| L&D Sky High Roofing Limited | Construction | 2023 |
| L&L Esther Limited Limited | Transport & logistics | 2024 |
| Lahore Restaurant Watford Limited | Hospitality | 2017 |
| Langford Ultrasonics Limited | Extraterritorial | 2000 |
| Large S P Limited | Information & communication | 2010 |
| Large Screen Print Limited | Manufacturing | 2002 |
| Lase Properties Ltd | Real estate | 2025 |
| Laser 101 Limited | Other services | 2023 |
| LCT Property Investments Ltd | Financial services | 2025 |
| LEA Jayne Webber Limited | Administrative & support | 2012 |
| Leamington Barber Ltd | Other services | 2023 |
| LED Smart Ltd | Wholesale & retail | 2019 |
| LEE Cowell Property Lettings Limited | Hospitality | 2019 |
| LEE Parker Plant Ltd | Construction | 2013 |
| Leesha Irwin Art Psychotherapy Limited | Health & social care | 2021 |
| Leeson-Steele Consulting Ltd | Public administration | 2026 |
| Legal R Ltd | Professional & scientific | 2015 |
| Lekh Transport Limited | Transport & logistics | 2025 |
| Lewis Halfacree Heating & Plumbing Ltd | Construction | 2024 |
| Lfmc Consulting Ltd | Information & communication | 2025 |
| LGI Electrical Ltd | Construction | 2013 |
| Life Church (Europe) | Other services | 2010 |
| Life Comfort Products Limited | Wholesale & retail | 2009 |
| Lincoln Farm Park Limited | Hospitality | 1986 |
| Linkline Parcel Express Limited | Real estate | 1990 |
| LJ Fleet Services Ltd | Wholesale & retail | 2025 |
| LJH Marketing Solutions Ltd | Professional & scientific | 2018 |
| LJN Building Services Ltd | Construction | 2026 |
| Loft Services Ltd | Construction | 2025 |
| Lofted Construction Ltd | Construction | 2018 |
| Londonsbridge Ltd | Construction | 2017 |
| Long Shen Limited | Administrative & support | 2022 |
| Losh Grill Limited | Hospitality | 2023 |
| Love of Cars Ltd | Wholesale & retail | 2025 |
| LSA Group Ltd | Manufacturing | 2022 |
| LTG Connect Ltd | Administrative & support | 2026 |
| Lukilepak Ltd | Transport & logistics | 2016 |
| Luminaris Advisory Limited | Professional & scientific | 2026 |
| Lynbrook Services Limited | Manufacturing | 2015 |
| Lyric Logistics Limited | Transport & logistics | 2023 |
| M J Turner Engineering Limited | Professional & scientific | 2025 |
| M LIP Trans Ltd | Transport & logistics | 2024 |
| M Pascal Construction Ltd | Construction | 2018 |
| M Quinn Building Projects Limited | Construction | 2015 |
| M V S D Limited | Wholesale & retail | 2024 |
| M Z Transport Ltd | Transport & logistics | 2012 |
| M&Dclearanceandmaintenance Ltd | Transport & logistics | 2024 |
| M&J's Blooming Gardens Ltd | Administrative & support | 2024 |
| M&M Professional Builders Ltd | Construction | 2023 |
| M. & M. Hotels Limited | Hospitality | 1996 |
| M. Vicary Decorating Contractor Ltd | Construction | 2014 |
| M.C.S. Cleaning Midlands Ltd | Administrative & support | 2017 |
| M.R.L. Consultancy Limited | Information & communication | 1994 |
| M.S Plumbing Solutions Limited | Manufacturing | 2016 |
| M.S.F. Engineering Ltd | Manufacturing | 1998 |
| M.T.A Engineering Limited | Professional & scientific | 2020 |
| M2R Business Solutions Ltd | Professional & scientific | 2023 |
| Macgas Heating Ltd | Construction | 2022 |
| Mackay-Miller Electronics Ltd | Construction | 2015 |
| Madan Traders Ltd | Wholesale & retail | 2025 |
| Madrina Limited | Information & communication | 1999 |
| MAID2CLEAN (Sutton Coldfield) Limited | Administrative & support | 2015 |
| MAID2CLEAN Cumbria Limited | Administrative & support | 2010 |
| Main Street Property Ltd | Real estate | 2025 |
| Makch 10 Limited | Construction | 2023 |
| Makch Build Limited | Construction | 2023 |
| Makepeace Property Ltd | Real estate | 2024 |