| Kaymax Surfacing Limited | Construction | 2016 |
| KB Entertainment Limited | Information & communication | 2023 |
| Keimar Associates Ltd | Administrative & support | 2014 |
| Kellington Group Limited | Wholesale & retail | 2018 |
| Kelly Enterprises Ltd | Education | 2015 |
| KEN S Legacy Ltd | Real estate | 2025 |
| KEN Shepherd & Sons Limited | Transport & logistics | 2004 |
| Kenchen (Stamford) Limited | Hospitality | 2016 |
| Kencom Engineering Ltd | Professional & scientific | 2016 |
| Kennington Haulage Ltd | Transport & logistics | 2026 |
| Kennington Spriggs Hire Ltd | Administrative & support | 2025 |
| Kettering and Corby Broadcasting Company Ltd | Information & communication | 2024 |
| KEW Medical Aesthetics Ltd | Health & social care | 2024 |
| Keystone Academy Trust | Education | 2011 |
| KG Windows & Doors Ltd | Construction | 2023 |
| KH and HS Properties Limited | Real estate | 1997 |
| KH Developments Beccles Limited | Extraterritorial | 2021 |
| KH Developments East Midlands Ltd | Water & waste | 2019 |
| KH Developments Sibson Limited | Extraterritorial | 2021 |
| Khanal Property Limited | Real estate | 2025 |
| Kingfisher Ventures Limited | Professional & scientific | 2008 |
| Kingsfoil Land Advisory Ltd | Professional & scientific | 2026 |
| Kingston Upon Hull City Transport Limited | Extraterritorial | 2023 |
| Kingswood Builders (Lincolnshire) Limited | Construction | 1998 |
| Kiptime Ltd | Real estate | 2022 |
| Kirby Lets Ltd | Real estate | 2020 |
| Kirby Lettings Ltd | Real estate | 2018 |
| Kitman UK (Stamford) Limited | Wholesale & retail | 2018 |
| KMP Business Ltd | Administrative & support | 2026 |
| Knapp Properties Ltd | Construction | 2015 |
| KNI Consulting Services Ltd | Professional & scientific | 2014 |
| Knotts Close Management Company Limited | Households | 2008 |
| KP CAD Design Ltd | Professional & scientific | 2013 |
| KP Holbeach Electrical Ltd | Construction | 2012 |
| KRG Consultancy Ltd | Information & communication | 2024 |
| Kristian Newman Bar Ltd | Hospitality | 2018 |
| KW Web Studio Ltd | Information & communication | 2026 |
| L & J Hospitality Ltd. | Hospitality | 2008 |
| L B Finance Solutions Ltd | Financial services | 2018 |
| L S Baker Limited | Other services | 1998 |
| L.Green-Brickwork Ltd | Construction | 2025 |
| L.J. Roberts (Timber) Limited | Wholesale & retail | 2020 |
| LA Grotta Collective Ltd | Wholesale & retail | 2019 |
| Laidler Design Ltd | Professional & scientific | 2025 |
| Lakeview Dog Adventure Park Ltd | Other services | 2023 |
| Lamberts Estates Limited | Agriculture & fishing | 1945 |
| Landvise Ltd | Real estate | 2026 |
| Lark Connections Limited | Energy | 2015 |
| Lark Energy Asset Holdings Limited | Extraterritorial | 2016 |
| Lark Energy Holdings Limited | Financial services | 2011 |
| Lark GAS Assets Limited | Energy | 2016 |
| Lark Power Development Limited | Construction | 2014 |
| Lark Power Group Limited | Financial services | 2017 |
| Lark Power Services Limited | Energy | 2012 |
| Larkfleet Elevating House Limited | Construction | 2016 |
| Larkfleet Flood Safe House Limited | Extraterritorial | 2021 |
| Larkfleet Group Holding Company Limited | Financial services | 2025 |
| Larkfleet Group Limited | Professional & scientific | 2015 |
| Larkfleet Group X House Limited | Extraterritorial | 2021 |
| Larkfleet Limited | Construction | 1998 |
| Larkfleet Smart Homes Limited | Energy | 2014 |
| Larkfleet Smart Homes Trading Ltd | Financial services | 2023 |
| Larkfleet X House Limited | Extraterritorial | 2021 |
| Laser Filters UK Ltd | Wholesale & retail | 2007 |
| Latimer Living Limited | Professional & scientific | 2017 |
| Launchpad Technology Ltd | Information & communication | 2026 |
| Lawrence Coulson Ltd | Arts & recreation | 2011 |
| Lawton Property Investments Ltd | Real estate | 2022 |
| Lcmb Therahealth Homecare Ltd | Health & social care | 2014 |
| LCN Transport Ltd | Transport & logistics | 2020 |
| LEA Wenban Ltd | Information & communication | 2019 |
| Lean Journey Consultancy Ltd | Professional & scientific | 2025 |
| Lees Scaffolding Services Limited | Construction | 2003 |
| Lets Agreed Ltd | Real estate | 2020 |
| Leverton Brothers Limited | Agriculture & fishing | 2016 |
| Lexmar Autos Ltd | Wholesale & retail | 2015 |
| Leyland Creative Limited | Information & communication | 2022 |
| LH Hold Co Ltd | Agriculture & fishing | 2021 |
| Lightbox 84 Ltd | Education | 2026 |
| Lincolnshire Bidco Limited | Other services | 2024 |
| Lincolnshire Midco Limited | Other services | 2024 |
| Lincolnshire Topco Limited | Other services | 2024 |
| Lincs Building Ltd | Construction | 2021 |
| Lincs Business Services Ltd | Administrative & support | 2010 |
| Lincs Engineering Solutions Ltd | Professional & scientific | 2021 |
| Lincs Garage Door Services Ltd | Construction | 2012 |
| Link-Into-Leisure Limited | Arts & recreation | 2003 |
| Liquidmoni Ltd | Financial services | 2023 |
| Liquiscreed Ltd | Construction | 2022 |
| Little Lotus Stories Ltd | Information & communication | 2025 |
| Livinjoy Ltd | Health & social care | 2023 |
| LJT Enterprise Limited | Extraterritorial | 2017 |
| LLD Designz Ltd | Information & communication | 2026 |
| LMR Couriers Ltd | Transport & logistics | 2019 |
| Locks Direct Limited | Extraterritorial | 2003 |
| LON Bull Marketing Ltd | Wholesale & retail | 2011 |
| LP Flooring Ltd | Construction | 2026 |
| Lsnv Property Ltd | Real estate | 2026 |
| Lucid Media Productions Ltd | Information & communication | 2025 |
| Lumb Associates Ltd | Manufacturing | 2011 |