| K J B Consultants Limited | Professional & scientific | 2007 |
| K W Properties (NW) Limited | Construction | 2017 |
| K.C. Hire and Sales Limited | Administrative & support | 1985 |
| K.F.Pilotage Services Ltd | Transport & logistics | 2012 |
| Kabila House Limited | Health & social care | 2022 |
| Kaizen FM Group Ltd | Water & waste | 2022 |
| Kampa Advisors Limited | Professional & scientific | 2022 |
| Kapra Falconeri Limited | Wholesale & retail | 2022 |
| KAR Sales & Marketing Limited | Administrative & support | 2024 |
| Karida Living Limited | Professional & scientific | 2015 |
| Karmarcia Ltd | Professional & scientific | 2021 |
| KC Programming Limited | Manufacturing | 2014 |
| Kearsley Ltd | Administrative & support | 2026 |
| Keene Instrumentation Limited | Administrative & support | 2014 |
| Kelher Supplies Limited | Wholesale & retail | 2002 |
| Kemosabe Ltd | Information & communication | 2012 |
| Kennington Technical Limited | Professional & scientific | 2010 |
| Kevin O'Grady Limited | Health & social care | 2023 |
| Kid's Space Limited | Education | 2018 |
| Kimpton Ltd | Construction | 1963 |
| Kingsmead Projects Limited | Professional & scientific | 2015 |
| Kinnord Limited | Professional & scientific | 2006 |
| Kirkby JIG & Tool Company Limited | Manufacturing | 1955 |
| Kirkman Engineering Limited | Construction | 2013 |
| Kitchenware Express Limited | Wholesale & retail | 2019 |
| Kjma Projects Limited | Administrative & support | 2013 |
| KKP Recruitment for Adult Education Ltd | Professional & scientific | 2018 |
| KLM Plant Limited | Administrative & support | 2008 |
| KMS Technology Limited | Administrative & support | 2026 |
| Kopcot Ltd | Real estate | 2019 |
| KP ENG Limited | Other services | 1992 |
| KQ Social Limited | Professional & scientific | 2025 |
| Kris Thompson Ltd | Health & social care | 2014 |
| Kutang Ltd | Information & communication | 2019 |
| L&L Solutions Limited | Professional & scientific | 2015 |
| L.M.S. Complete Limited | Administrative & support | 2025 |
| Lady C Property Ltd | Real estate | 2018 |
| Lancopak Limited | Administrative & support | 2005 |
| Lanzarote Villa Choice Limited | Administrative & support | 2015 |
| Laser Parts Direct Limited | Wholesale & retail | 2010 |
| Laser Patterns NW Limited | Construction | 2021 |
| Last MAN Stands Berkshire Limited | Arts & recreation | 2026 |
| Last MAN Stands Limited | Arts & recreation | 2004 |
| Last MAN Stands UK Ltd | Arts & recreation | 2010 |
| LBW Corporate Advice Limited | Administrative & support | 2011 |
| LCH Bunbury Limited | Construction | 2021 |
| LCH Daresbury Hall Limited | Construction | 2022 |
| LCH DEE View Limited | Construction | 2022 |
| Ld&S Investments Ltd | Financial services | 2024 |
| LEA Building Services Ltd | Administrative & support | 2007 |
| Leaf and Vine Ltd | Wholesale & retail | 2021 |
| Leaver Properties Ltd | Real estate | 2025 |
| LEE Engineering Design Limited | Administrative & support | 2000 |
| Leed Development Ltd | Professional & scientific | 2014 |
| LES Hill Flooring Limited | Wholesale & retail | 2007 |
| LET Wirral Limited | Real estate | 2020 |
| Lethq Limited | Financial services | 2016 |
| Lewis Reed (WAV) Ltd | Wholesale & retail | 1999 |
| LG Home Rewire & Electrical Services Ltd | Construction | 2023 |
| Liberty Property Rentals Ltd | Real estate | 2020 |
| Liburd Expediting Limited | Administrative & support | 2019 |
| Lions Rugby Club Limited | Wholesale & retail | 2022 |
| Lister Carter Homes Limited | Real estate | 2014 |
| Little Diva Ltd | Arts & recreation | 2020 |
| Littledivafranchising Ltd | Arts & recreation | 2020 |
| Livent UK Pension Plan Limited | Administrative & support | 2001 |
| Liverpool Pilotage Services Limited | Administrative & support | 1997 |
| Liverpool Rhinology Ltd | Health & social care | 2024 |
| LJC One Limited | Professional & scientific | 2017 |
| Lloyd Savage Limited | Professional & scientific | 2007 |
| LMS Global Enterprises Limited | Administrative & support | 2011 |
| LMS SW Ltd | Arts & recreation | 2008 |
| Logicresponse Limited | Construction | 1991 |
| Lolly Investments Ltd | Financial services | 2024 |
| Longhurst's Laundry & Cleaning Ltd | Administrative & support | 2023 |
| Lord Dermott Ltd | Arts & recreation | 2022 |
| Lord Nelson Design Limited | Professional & scientific | 2007 |
| Loxstone Buckley Ltd | Construction | 2020 |
| Ludo Software Limited | Professional & scientific | 2025 |
| Luna Events (Northwest) Ltd | Administrative & support | 2017 |
| Lupa Engineering Ltd | Administrative & support | 2012 |
| LV Nauta Pilotage Services Ltd | Transport & logistics | 2017 |
| M a H Services Limited | Administrative & support | 2007 |
| M Hopkinson Roofing Services Limited | Construction | 2019 |
| M. a. W. Electrical Limited | Construction | 2002 |
| M. G. Building Services Limited | Water & waste | 2003 |
| Macdowall Interiors Limited | Professional & scientific | 2026 |
| Magma Industries Limited | Administrative & support | 2018 |
| Magnusfilm Limited | Information & communication | 2014 |
| Mammut Hire Limited | Administrative & support | 2020 |
| Martin Dagnall Electrical Ltd | Professional & scientific | 2007 |
| Marunz Care Ltd | Health & social care | 2025 |
| Mary Louise Campbell Limited | Professional & scientific | 2018 |
| Massey Radiology Limited | Health & social care | 2019 |
| Matcad Ltd | Professional & scientific | 2016 |
| MAY Butterflies Limited | Administrative & support | 2019 |
| MB Brands Limited | Wholesale & retail | 2010 |
| MB Resi Flow Limited | Construction | 2026 |
| MBF Print Services Limited | Manufacturing | 2007 |
| MBJ Aviation Limited | Administrative & support | 2013 |