| JTG (Cheshire) Limited | Hospitality | 2006 |
| Just Paint Ltd | Wholesale & retail | 2026 |
| Just US Then Ltd | Information & communication | 2024 |
| JW Motion Ltd | Professional & scientific | 2015 |
| K. E. S. Electrical Services Limited | Construction | 2005 |
| K1 Consulting Limited | Professional & scientific | 2025 |
| Kage Design Services Ltd | Information & communication | 2016 |
| Kaizen Windows & Doors Limited | Construction | 2025 |
| Kartebia Enterprises Limited | Professional & scientific | 2019 |
| Katy Parr Coaching Limited | Professional & scientific | 2023 |
| KB Components Limited | Wholesale & retail | 2004 |
| KCB Holdings Limited | Construction | 2018 |
| Keko DEP Ltd | Hospitality | 2025 |
| KEN Nicholson Ltd | Construction | 2003 |
| Kevin Llewelyn-Evans Ltd | Professional & scientific | 2010 |
| Kevin Thelwell Limited | Construction | 2017 |
| Kevob Limited | Construction | 2013 |
| Key LET Limited | Real estate | 1998 |
| Keypower Energy Ltd | Extraterritorial | 2019 |
| KG Electricals Group Limited | Manufacturing | 2025 |
| Kinetic Selling Ltd | Education | 2019 |
| Kingfisher Environmental Solutions Limited | Real estate | 1996 |
| Kingsclere Design and Print Limited | Manufacturing | 2001 |
| Kingsley Financial Management Limited | Administrative & support | 2003 |
| Kingsley Fish Bar 1 Ltd | Wholesale & retail | 2020 |
| Kingsview Homes Limited | Health & social care | 1999 |
| Kirovia Limited | Hospitality | 2025 |
| Kitching Collins Limited | Real estate | 2011 |
| Kiwi Anaesthesia Ltd | Health & social care | 2017 |
| Kjbp Limited | Extraterritorial | 2013 |
| KMI Investments Limited | Real estate | 2022 |
| Knightstor Limited | Administrative & support | 2005 |
| Knutsford Propco Limited | Real estate | 2025 |
| Kova Medical Limited | Health & social care | 2014 |
| KS Property Lettings Limited | Real estate | 2023 |
| Kudos Coffee (Stockbridge) Ltd | Hospitality | 2013 |
| Kudos Coffee Ltd | Hospitality | 2017 |
| Kumu Clothing Limited | Wholesale & retail | 2018 |
| Kurdish Golden CUT Ltd | Other services | 2025 |
| Kwazar UK Limited | Wholesale & retail | 2013 |
| Labtec (Avian) Limited | Extraterritorial | 2010 |
| Lamdad Securities Limited | Real estate | 1982 |
| Landmill Limited | Real estate | 1990 |
| Laundry Yard Ltd | Other services | 2015 |
| Laverstoke and Freefolk Millennium Green Limited | Professional & scientific | 2011 |
| Laverstoke Game Services Limited | Agriculture & fishing | 2002 |
| LB Caravan Services Limited | Manufacturing | 2016 |
| LBV Holdings Limited | Financial services | 2026 |
| LBV Property Limited | Real estate | 2026 |
| LBV Trading Limited | Real estate | 2026 |
| Lcmc Ltd | Real estate | 2012 |
| LE Hardy Global Ltd | Professional & scientific | 2021 |
| Leather Missal Covers Ltd | Manufacturing | 2026 |
| LEC Park Limited | Information & communication | 2015 |
| LEE Gleeson Ltd | Transport & logistics | 2021 |
| Legends in Thread Limited | Wholesale & retail | 2023 |
| Leisure & Retail Developments Limited | Extraterritorial | 2004 |
| Lello Enterprises Ltd | Wholesale & retail | 2026 |
| Lentulus Properties Limited | Health & social care | 2014 |
| LEO James Property Limited | Real estate | 2026 |
| Leonard Projects Ltd | Information & communication | 2026 |
| Lewitt Consulting Limited | Administrative & support | 2012 |
| LHD Contract Services Limited | Construction | 2024 |
| Liam Finch Transport Limited | Transport & logistics | 2025 |
| Lighteach Estate Management Ltd | Households | 2023 |
| Lily's Beauty Salon Ltd | Other services | 2025 |
| Linnwood Construction Limited | Construction | 2024 |
| Lipa Care Limited | Financial services | 2023 |
| Little Beginnings Group Limited | Wholesale & retail | 2022 |
| Little Village GRP Shropshire Limited | Construction | 2012 |
| Livwell Healthcare Ltd | Health & social care | 2023 |
| Llewellyn Homes Limited | Households | 2025 |
| Llewellyns Limited | Professional & scientific | 2009 |
| Llews Casa Limited | Real estate | 2026 |
| Llithyia Holdings Limited | Professional & scientific | 2016 |
| Lloyd James Property Ltd | Construction | 2026 |
| Lloyd Watson Haulage Limited | Transport & logistics | 2005 |
| LMC Stairlift Services Limited | Construction | 2025 |
| Lockgate Cafe Ltd | Real estate | 2012 |
| Loli Holdings Limited | Financial services | 2026 |
| Lolly & BOO Ltd | Wholesale & retail | 2018 |
| London Prime Property Agents Ltd | Real estate | 2021 |
| Longacre Lettings LLP | | 2021 |
| Loose Ends Salon Ltd | Other services | 2017 |
| Lords & Co Property Management Ltd | Real estate | 2024 |
| Loud and Soft Limited | Manufacturing | 1997 |
| Love Cheese Live Ltd | Administrative & support | 2020 |
| Love Wins Events Ltd | Arts & recreation | 2025 |
| Love Your Rental Ltd | Real estate | 2025 |
| Lowe Brokers Limited | Wholesale & retail | 2018 |
| Lower Farm Barns Management Company Limited | Households | 2014 |
| Lucia MAY Holdings Limited | Financial services | 2024 |
| Lucy Marsh Interiors Limited | Professional & scientific | 2023 |
| Lunan Solutions Ltd | Wholesale & retail | 2026 |
| Lunar Construction Limited | Construction | 2024 |
| Luxury Retreat Properties Limited | Hospitality | 2024 |
| Luya Agency Limited | Professional & scientific | 2017 |
| Lyon Made Limited | Wholesale & retail | 2003 |
| M & a Cooper Limited | Real estate | 2017 |
| M Ellis Building Services Ltd | Manufacturing | 2021 |