| Just Spaces Ltd | Real estate | 2019 |
| K M Gisborne Associates Limited | Education | 2008 |
| Kacift Store Ltd | Wholesale & retail | 2025 |
| Kelly Fletcher Aesthetic Room Ltd | Health & social care | 2021 |
| Kenilworth Place Limited | Real estate | 2021 |
| Kenny Brakes Joinery & Building Services Ltd | Construction | 2024 |
| Keren Baines Podiatry Limited | Health & social care | 2012 |
| Ketone Group Ltd | Professional & scientific | 2024 |
| Kevin G Mather Holdings Limited | Real estate | 2019 |
| Kevin G Mather Traction Services Limited | Transport & logistics | 2014 |
| Key Engineering (Chesterfield) Limited | Manufacturing | 2009 |
| Keycove Ltd | Manufacturing | 2025 |
| Keyworth Propert Ltd | Real estate | 2019 |
| Kiam Interiors Limited | Construction | 2023 |
| Killer-Byte Ltd | Information & communication | 2013 |
| Kilner Holdings Limited | Professional & scientific | 2007 |
| Kilner Vacuumation Company Limited | Manufacturing | 1964 |
| Kingswood Design & Construction Ltd | Construction | 2015 |
| KJS Digital Transformation Ltd | Information & communication | 2019 |
| KNH Investment Management Ltd | Extraterritorial | 2014 |
| Knight & Knight Properties Limited | Real estate | 2021 |
| Knowles Farm Equestrian & Agricultural Services Ltd | Agriculture & fishing | 2012 |
| Kotwf Ltd | Education | 2020 |
| KPM Design Limited | Professional & scientific | 2019 |
| KRM Store Ltd | Wholesale & retail | 2025 |
| KS Gardens Management Company Limited | Real estate | 2019 |
| Ksquared Solutions Limited | Real estate | 2025 |
| Kuci Design Limited | Construction | 2015 |
| Kuscular Limited | Hospitality | 2024 |
| L M C NO 1 Limited | Households | 2021 |
| L M C NO 2 Limited | Households | 2021 |
| L.B Roofing Building Solutions Ltd | Construction | 2025 |
| Laboratory Ovens Ltd | Wholesale & retail | 2025 |
| Lakelands Developments Limited | Construction | 2003 |
| Lakes Edge Ltd | Other services | 2025 |
| Lakeside Electrical Limited | Construction | 2003 |
| Land & Property Services Ltd | Construction | 2025 |
| Langhammer Limited | Households | 1989 |
| Laybus Limited | Agriculture & fishing | 1975 |
| Le'Mont Fixings and Installations Ltd | Construction | 2021 |
| Leak Testing Ltd | Construction | 2015 |
| Leikya Ltd | Wholesale & retail | 2021 |
| Leisure Attraction Services Ltd | Other services | 2018 |
| Lets Go Events Ltd | Administrative & support | 2018 |
| LEX Substation Services Ltd | Manufacturing | 2016 |
| Liam Allen Consultancy Services Ltd | Professional & scientific | 2016 |
| Libra Twenty One Limited | Professional & scientific | 2024 |
| Link 2 Equipment Solutions Limited | Wholesale & retail | 2013 |
| LINK2 Simpler Recycling Ltd | Extraterritorial | 2025 |
| Linking Outdoors and Music C.I.C. | Education | 2026 |
| Little Bear Coaching & Consulting Ltd | Professional & scientific | 2024 |
| Little Bloom Bounce Ltd | Arts & recreation | 2024 |
| Littlefeet Childcare Limited | Health & social care | 2011 |
| Livs Card Emporium Ltd | Wholesale & retail | 2024 |
| LK Chase Ltd | Real estate | 2023 |
| Locksley Hotels Limited | Hospitality | 2019 |
| Logan's Liquor Stores Ltd | Wholesale & retail | 2024 |
| Longcroft Handyman Services Ltd | Other services | 2025 |
| Love Your Boiler Limited | Construction | 2015 |
| LTZ Pharma Ltd | Wholesale & retail | 2018 |
| Lubeline Limited | Manufacturing | 2001 |
| Lynley International Limited | Information & communication | 2012 |
| M & I Professional Protection Products Ltd | Extraterritorial | 2018 |
| M B Plant Hire Services Limited | Administrative & support | 2010 |
| M C Loxley Limited | Construction | 2018 |
| M J F Assets Limited | Administrative & support | 2015 |
| M&M Properties Group Ltd | Real estate | 2025 |
| Mabolo Ltd | Information & communication | 2012 |
| MAD About Saffron Ltd | Professional & scientific | 2024 |
| Mahir Engineering Ltd | Professional & scientific | 2022 |
| Mahir Traders Limited | Wholesale & retail | 2025 |
| Mahsirat Ltd | Health & social care | 2015 |
| Mainstay Counselling Ltd | Education | 2025 |
| MAM82 Ltd | Health & social care | 2026 |
| Managed Power Solutions Ltd | Construction | 2018 |
| Mapp Developments Limited | Agriculture & fishing | 1997 |
| Mapp Kitchens & ALE Limited | Hospitality | 2014 |
| MAR Engineering Limited | Construction | 2018 |
| Marco G Cosmetics House Ltd | Wholesale & retail | 2017 |
| Mardin Cutz Ltd | Other services | 2024 |
| Margaret Rose Limited | Real estate | 2016 |
| Mark Rumney Financial Services Ltd | Financial services | 2015 |
| Marleak Ltd | Households | 2024 |
| Massive Construction Ltd | Construction | 2023 |
| Massive Investments Ltd | Construction | 2025 |
| Massive Regeneration Ltd | Construction | 2025 |
| Massive Rise Ltd | Construction | 2025 |
| Matilda Project Limited | Construction | 2006 |
| Matt's Electrical Services Limited | Other services | 2017 |
| Mattair Maintenance Limited | Construction | 2012 |
| Mavi Works Ltd | Administrative & support | 2019 |
| Maximum Controls Limited | Professional & scientific | 1971 |
| MAY Motors UK Ltd | Wholesale & retail | 2023 |
| MB Digital Post Production Limited | Professional & scientific | 2018 |
| Mccrudden Training Ltd | Administrative & support | 2011 |
| Mechu Limited | Hospitality | 2016 |
| Mediclinix Ltd | Health & social care | 2026 |
| Megaseller Ltd | Wholesale & retail | 2023 |
| Mekong Made Limited | Wholesale & retail | 2025 |
| Mercful Limited | Real estate | 2022 |