| Kenpas Vision Limited | Wholesale & retail | 2024 |
| Keppel Gate Developments Limited | Real estate | 2022 |
| Kesa Technology Limited | Information & communication | 2026 |
| Kewfab Ltd | Manufacturing | 2020 |
| Keyhome Property Management Ltd | Real estate | 2021 |
| KFF Holdings Ltd | Real estate | 2022 |
| KGB Estates Limited | Real estate | 2018 |
| Khosrow Dental Legacy Ltd | Health & social care | 2025 |
| KI Coaching Limited | Health & social care | 2025 |
| KI Traffic Management Ltd | Construction | 2017 |
| Kiings Barber 8 Ltd | Other services | 2026 |
| Kildrum Care Ltd | Health & social care | 2020 |
| Kimabby Properties Ltd | Real estate | 2025 |
| Kingfisher Lakeside Bar Limited | Hospitality | 2025 |
| Kirk Johnstone Media Limited | Arts & recreation | 2025 |
| KJ Properties KJ Limited | Households | 2025 |
| KJP Finance Ltd | Professional & scientific | 2021 |
| KK Used Cars Limited | Wholesale & retail | 2008 |
| Klub Hause Group Ltd | Other services | 2026 |
| KM01 Ltd | Real estate | 2025 |
| KM02 Ltd | Real estate | 2025 |
| KM03 Ltd | Real estate | 2025 |
| KM04 Ltd | Real estate | 2025 |
| Kmaras Ltd | Hospitality | 2017 |
| KMR Properties Ltd | Real estate | 2018 |
| KMS Hardrange Holdings Limited | Financial services | 2023 |
| KMS Hardrange Limited | Manufacturing | 2006 |
| Knpv Limited | Health & social care | 2025 |
| Kombi-Nation Campers Limited | Wholesale & retail | 2021 |
| Komur Catering Limited | Hospitality | 2017 |
| Kootoo Digital Ltd | Administrative & support | 2019 |
| KP Swim School LLP | | 2026 |
| KP Taylor Holdings Limited | Professional & scientific | 2025 |
| KR Rendering Ltd | Construction | 2020 |
| Kraken Finance UK Ltd | Financial services | 2023 |
| Kranthi & Tulasi Nasani Limited | Health & social care | 2020 |
| Kravings Peri Peri Ltd | Hospitality | 2025 |
| Krish Retail Stores Ltd | Wholesale & retail | 2019 |
| Krishna & Kiara Nasani Ltd | Health & social care | 2024 |
| KRR Aesthetics Limited | Health & social care | 2024 |
| Kruger Bidco Limited | Financial services | 2020 |
| Kruger Midco Limited | Financial services | 2024 |
| Kruger Topco Limited | Financial services | 2024 |
| Krum Limited | Transport & logistics | 2017 |
| KSR & FKR Ltd | Real estate | 2024 |
| KST Cladding Ltd | Construction | 2025 |
| Kudos Solutions Ltd | Extraterritorial | 2015 |
| Kusten Limited | Real estate | 2024 |
| Kyberia Limited | Administrative & support | 2018 |
| L and T MOT Limited | Wholesale & retail | 2015 |
| L C Social Work Services Ltd | Health & social care | 2022 |
| L Haje Store Ltd | Wholesale & retail | 2026 |
| L Murphy Safety Services Limited | Health & social care | 2016 |
| L Rumsby Logistics Consultants Limited | Professional & scientific | 2005 |
| L&A Property Group Ltd | Real estate | 2020 |
| L&R Cleaning Group Ltd | Administrative & support | 2019 |
| L. & R. Roadlines Limited | Construction | 1984 |
| L.T.G. (Cheshire) Ltd | Manufacturing | 2008 |
| L4V Group Holdings Limited | Financial services | 2023 |
| LA Line Marking Ltd | Construction | 2025 |
| Labineers Limited | Wholesale & retail | 2023 |
| Lache Village Works | Education | 2013 |
| Ladder Down Ltd | Professional & scientific | 2022 |
| Ladybird Catering Limited | Hospitality | 2023 |
| Ladybird Lettings Limited | Real estate | 2009 |
| Laguna Partners Limited | Administrative & support | 2011 |
| Lake View Livery Ltd | Arts & recreation | 2025 |
| Lakeland Holiday Home Ltd | Hospitality | 2019 |
| Laker Vent Engineering Limited | Construction | 1986 |
| Lancashire Smiles Limited | Health & social care | 2021 |
| Largacci Ltd | Information & communication | 2026 |
| Laser by Kirstie Ltd | Other services | 2022 |
| Laser Frame Ltd | Extraterritorial | 2018 |
| Lata Property Services Limited | Real estate | 2018 |
| Latform Auto Ltd | Wholesale & retail | 2025 |
| Laura Spence Limited | Education | 2023 |
| Laureal Ltd | Real estate | 2024 |
| Lavelle Corrugated Ltd | Professional & scientific | 2024 |
| Layered Collective Beauty Ltd | Other services | 2024 |
| LB Electrical Solutions U.K Ltd | Construction | 2026 |
| LB Fitness Services Ltd | Arts & recreation | 2013 |
| LC Enduro Club Limited | Administrative & support | 2021 |
| LCG Props Ltd | Information & communication | 2022 |
| Lcmg Limited | Financial services | 2008 |
| LD Civils and Groundwork Ltd | Construction | 2017 |
| LD Civils Ltd | Construction | 2021 |
| LD Plant Hire Limited | Construction | 2021 |
| LD Robinson (1999) Limited | Hospitality | 2023 |
| Leach Particle Technologies Ltd | Professional & scientific | 2024 |
| Leadsave AI Ltd | Information & communication | 2026 |
| Leadworks Quantity Surveying Limited | Professional & scientific | 2007 |
| Learning Nexus Limited | Education | 2016 |
| Learning Path Digital Limited | Manufacturing | 2019 |
| LED by Design Ltd | Manufacturing | 2010 |
| Ledsham (NW) Ltd | Hospitality | 2019 |
| Ledsham Group Holdings Limited | Financial services | 2024 |
| Ledsham Heating Ltd | Construction | 2021 |
| Ledsham Holdings Limited | Real estate | 2017 |
| Ledsham Property Ltd | Real estate | 2025 |
| Leeds Dental Care Limited | Health & social care | 2017 |