| Knotts Place Management Company Limited | Hospitality | 1966 |
| KOA Property Group Limited | Real estate | 2019 |
| KOC Ltd | Agriculture & fishing | 2024 |
| KOH Samui UK Limited | Real estate | 2021 |
| Konas Development Limited | Real estate | 2025 |
| Konas Enterprises Ltd | Transport & logistics | 2015 |
| Konas Holdings Limited | Financial services | 2024 |
| Konas Management Limited | Transport & logistics | 2021 |
| Kongcrete Ltd | Construction | 2022 |
| Konor's Fish and Chips Ltd | Hospitality | 2021 |
| Kontechs Limited | Information & communication | 2020 |
| KOR Plant Limited | Construction | 2014 |
| Kovora Compliance Group Ltd | Administrative & support | 2026 |
| Kovora Compliance Intelligence Platform Ltd | Information & communication | 2026 |
| Koyes Khan Holdings Ltd | Real estate | 2012 |
| Koyes Khan Hospitality Ltd | Hospitality | 2026 |
| Koze Estates Ltd | Real estate | 2022 |
| Kpfx Trading Limited | Administrative & support | 2025 |
| Kpmc Medical Limited | Health & social care | 2023 |
| Kprail Ltd | Extraterritorial | 2014 |
| KPS Services Ltd | Administrative & support | 2019 |
| Kraft Creations Ltd | Manufacturing | 2024 |
| KRB Rail Services Ltd | Construction | 2018 |
| Kredible Kleaner Limited | Administrative & support | 2024 |
| Krishna My Friend Ltd | Manufacturing | 2019 |
| KRP Developments Ltd | Construction | 2021 |
| KRT Contractors Ltd | Construction | 2023 |
| Krystal Klear Estates Ltd | Real estate | 2025 |
| KSA Architects Limited | Professional & scientific | 2002 |
| KSH Project Management Ltd | Administrative & support | 2024 |
| KT Accountants Ltd | Professional & scientific | 2017 |
| KTL Building Services Limited | Construction | 2014 |
| KU Medics Limited | Health & social care | 2024 |
| Kwik-Drop Limited | Wholesale & retail | 1999 |
| Kwiki Snacks Limited | Wholesale & retail | 2010 |
| Kyaneez Ltd | Hospitality | 2022 |
| Kynnex Ltd | Information & communication | 2021 |
| Kyoto TM Ltd | Construction | 2025 |
| Kyra J Limited | Real estate | 2023 |
| L & V Paving Limited | Administrative & support | 2016 |
| L . Marchant Brickwork Limited | Construction | 2021 |
| L a Electrical Services Southern Ltd | Construction | 2012 |
| L a Vape Ltd | Wholesale & retail | 2018 |
| L Alexander Investments Ltd | Real estate | 2020 |
| L B B Removals Ltd | Transport & logistics | 2023 |
| L C Wolfe Enterprises Limited | Administrative & support | 2016 |
| L D Ents Limited | Extraterritorial | 2018 |
| L D G Plastering Contractors Limited | Construction | 2019 |
| L D S Enterprises Ltd | Real estate | 2023 |
| L H Plastering Limited | Construction | 2017 |
| L H W Rail Solutions Limited | Transport & logistics | 2020 |
| L J Hynes Carpentry Ltd | Construction | 2024 |
| L R C Windows Ltd | Construction | 2024 |
| L R Construction Services Limited | Construction | 2022 |
| L S F Services Limited | Construction | 2021 |
| L&A Vision Property Ltd | Construction | 2026 |
| L&J Wigginton Ltd | Construction | 2026 |
| L&N Scaffolding Ltd | Construction | 2018 |
| L&Z Builders Ltd | Construction | 2024 |
| L'Ultima Ventures Ltd | Administrative & support | 2021 |
| L. Jackson Groundworks Ltd | Construction | 2006 |
| L.Toman Electrical Services Limited | Construction | 2009 |
| L47 Limited | Information & communication | 2025 |
| LA Performance Academy Limited | Education | 2024 |
| LAB99 Limited | Arts & recreation | 2018 |
| Labour Hire Services Limited | Financial services | 2018 |
| Laconic Collective Ltd | Professional & scientific | 2021 |
| Ladbury Health and Wellness Ltd | Other services | 2025 |
| Lady B'S Property Ltd | Real estate | 2025 |
| Lafiguera Properties Ltd | Real estate | 2022 |
| LAI Thai Services Limited | Information & communication | 2001 |
| Laker Property Maintenance Limited | Construction | 2002 |
| Lakes Business Consultants Ltd | Professional & scientific | 2017 |
| Lambourne Consultancy Ltd | Professional & scientific | 2025 |
| Lampi Capital Ltd | Financial services | 2022 |
| Lampi Investments Limited | Construction | 2025 |
| Lamplite Limited | Manufacturing | 2024 |
| Lamric Double Glazing Limited | Construction | 2018 |
| Lananh Ltd | Construction | 2024 |
| Land Electrical Limited | Construction | 2021 |
| Land Quest UK (Southern) Limited | Administrative & support | 2018 |
| Landbuild Brickwork Limited | Construction | 2022 |
| Landi Accounting Limited | Professional & scientific | 1999 |
| Landi Management Services Ltd | Professional & scientific | 2013 |
| Landingpad Invest UK Ltd | Administrative & support | 2025 |
| Landmillions Ltd | Construction | 2025 |
| Landtrekker UK Ltd | Wholesale & retail | 2022 |
| Lane Shift Recovery Ltd | Transport & logistics | 2026 |
| Lano Retreats Ltd | Health & social care | 2019 |
| Lanson Consultants Limited | Professional & scientific | 2002 |
| Lantana Catering Services Ltd | Hospitality | 2021 |
| Lantsco Limited | Transport & logistics | 2024 |
| Larn Pack Ltd | Administrative & support | 2018 |
| Larry's Lobster House Limited | Hospitality | 2014 |
| Larwood Associates Limited | Professional & scientific | 1999 |
| LAS Site Investigation Ltd | Construction | 2021 |
| Laser by LEN Ltd | Other services | 2024 |
| Lash GLO Ltd | Wholesale & retail | 2019 |
| Lashbase Ltd | Wholesale & retail | 2011 |
| Lashmar Computers Limited | Information & communication | 2021 |