| Koei Limited | Administrative & support | 2014 |
| Kogsf Trustee Limited | Education | 2012 |
| Kolaine's Beauty Lounge Ltd | Administrative & support | 2015 |
| Kolocalprivate Limited | Wholesale & retail | 2026 |
| Konas Kebab House Ltd | Hospitality | 2025 |
| Kopi Transport Limited | Transport & logistics | 2024 |
| Kovertek Limited | Manufacturing | 2013 |
| KP Prestige Ltd | Other services | 2022 |
| KR Medicare Ltd | Health & social care | 2023 |
| KR Property Sourcing Ltd | Real estate | 2026 |
| Kr.Eativ: Architects Ltd | Professional & scientific | 2011 |
| Kraken Enterprises Limited | Professional & scientific | 2015 |
| Krazy! Limited | Financial services | 2021 |
| Krfc Community Foundation C.I.C. | Arts & recreation | 2025 |
| Krieg Debt Collection Ltd. | Administrative & support | 2016 |
| Kris Trans Ltd | Transport & logistics | 2020 |
| Kronos Recruitment Ltd | Administrative & support | 2023 |
| Kruhn Engineering Ltd | Professional & scientific | 2023 |
| Krusada Teamwear Limited | Wholesale & retail | 2008 |
| Kruses Capital Group Ltd | Professional & scientific | 2006 |
| Krysnik Limited | Transport & logistics | 2009 |
| Kryten Products Ltd | Education | 2016 |
| KS84 Ltd | Wholesale & retail | 2025 |
| KSA Technology Limited | Information & communication | 2005 |
| KSB Associates Ltd | Professional & scientific | 2009 |
| KST Training Ltd | Education | 2026 |
| KTC Homes Ltd | Real estate | 2021 |
| Ktrl Ltd | Information & communication | 2018 |
| KTV Venue Stylists Ltd | Other services | 2019 |
| Kubbykraft Limited | Manufacturing | 2015 |
| Kubic Car Ltd | Wholesale & retail | 2021 |
| Kuboid Holdings Limited | Transport & logistics | 2021 |
| Kuboid Ltd | Transport & logistics | 2007 |
| Kundes Ltd | Hospitality | 2023 |
| Kupa Properties Ltd | Real estate | 2026 |
| Kurdish Hair Stylish Ltd | Other services | 2026 |
| Kurdish Quality Scissors Ltd | Other services | 2017 |
| Kurt Hobbs Coachworks Ltd | Administrative & support | 2009 |
| Kuzari Ltd | Professional & scientific | 2024 |
| Kvedaravicius Transport Limited | Extraterritorial | 2015 |
| KW Training and Nutrition Ltd | Extraterritorial | 2023 |
| Kwik-Nick Motors Ltd | Wholesale & retail | 2016 |
| Ky.Ca Ltd | Wholesale & retail | 2019 |
| Kyngswoode Services Limited | Administrative & support | 2014 |
| KZI Autoclinic Ltd | Wholesale & retail | 2024 |
| L & J Trading Limited | Wholesale & retail | 2015 |
| L & M Candles Ltd | Wholesale & retail | 2023 |
| L K Agri Limited | Extraterritorial | 2021 |
| L&A Inside ‘N’ OUT Ltd | Administrative & support | 2026 |
| L&R Asset Holdings Limited | Financial services | 2025 |
| L. a. Hire Limited | Construction | 2018 |
| L. S. Mortgages Limited | Financial services | 2011 |
| L.A.J Plumbing and Heating Ltd | Construction | 2021 |
| L.F. Builders Limited | Construction | 2003 |
| L.G.C.Interiors.Maintenance. Ltd | Households | 2025 |
| L.G.C.Interiors.Maintenance.Ltd Ltd | Construction | 2025 |
| L.M. Homeworks Ltd. | Construction | 2010 |
| L.T.K.Trust Co.Limited | Extraterritorial | 1945 |
| L2 Luxe Events Limited | Wholesale & retail | 2025 |
| LA Finance Service Limited | Professional & scientific | 2017 |
| LA Top Nails 68 Ltd | Other services | 2024 |
| LAB 2021 LLP | | 2021 |
| LAB Optimise Ltd | Professional & scientific | 2020 |
| Labra Tees Ltd | Wholesale & retail | 2025 |
| Labseed Ltd | Extraterritorial | 2024 |
| Labyrinth Property Ltd | Households | 2025 |
| Lacka Foods Limited | Manufacturing | 2012 |
| Lafe Thread Limited | Wholesale & retail | 2026 |
| Lafierce Ltd | Manufacturing | 2026 |
| Lagisetty Medical Services Ltd | Health & social care | 2013 |
| Lakeview Business Village Limited | Extraterritorial | 2006 |
| Lakhma ISO. Ltd | Manufacturing | 2024 |
| Lamont Utilities Limited | Professional & scientific | 2016 |
| Lamv Associates Ltd | Construction | 2016 |
| Lance Media Group Ltd | Information & communication | 2022 |
| Lanchester Land & Planning Limited | Real estate | 2011 |
| Land & Property Developers Ltd | Construction | 2022 |
| Landing Craft UK Limited | Wholesale & retail | 2017 |
| Langham Industrial Controls Limited | Manufacturing | 1996 |
| Langology Language Services Limited | Professional & scientific | 2021 |
| Langstrum Properties Ltd | Real estate | 2004 |
| Lanternlight Productions Ltd | Information & communication | 2018 |
| Larsson UK Limited | Wholesale & retail | 2011 |
| Latimer Barber Ltd | Other services | 2023 |
| Latimer Group Limited | Financial services | 2020 |
| Latitude Building Consultancy Limited | Professional & scientific | 2017 |
| LATITUDE53 Design Limited | Professional & scientific | 2023 |
| Laugh OUT Loud Theatre Company | Arts & recreation | 2018 |
| Laughing Bird Consulting Ltd | Professional & scientific | 2019 |
| Laura Arnold Therapy Limited | Other services | 2026 |
| Laura Jordan Ltd | Arts & recreation | 2012 |
| Laura Jordan Originals Ltd | Arts & recreation | 2021 |
| Laurel Mews Management Company Limited | Households | 1990 |
| Lauren Elizabeth Conveyancing Limited | Administrative & support | 2025 |
| Lauries House Ltd | Arts & recreation | 2014 |
| Lavanda Investments Limited | Real estate | 2024 |
| Lawclick Limited | Information & communication | 2020 |
| Lawyers Agency Services Limited | Extraterritorial | 2001 |
| Layer Cake Consulting Ltd | Professional & scientific | 2019 |
| Layton Trade Ltd | Other services | 2021 |