| JW Global Ltd | Wholesale & retail | 2024 |
| JWA Search Limited | Administrative & support | 2006 |
| JWC Capital Ltd | Financial services | 2022 |
| JWC Emporium Ltd | Wholesale & retail | 2025 |
| Jwgm Ltd | Financial services | 2024 |
| JWL Trading Limited | Wholesale & retail | 2024 |
| Jwln Limited | Wholesale & retail | 2026 |
| JZB Property Holdings Limited | Real estate | 2023 |
| JZP Investments Limited | Financial services | 2023 |
| K & B Motors Limited | Manufacturing | 2007 |
| K & D Agri | Financial services | 2024 |
| K & D Beattie Limited | Agriculture & fishing | 2024 |
| K & D Penguin Properties Limited | Real estate | 2021 |
| K & J Engineering Ltd | Professional & scientific | 2019 |
| K & J Hodge Contractors Ltd | Construction | 1995 |
| K & J Hodge Holdings Ltd | Financial services | 2023 |
| K & M Developments South West Ltd | Construction | 2013 |
| K & R Auto Services Limited | Wholesale & retail | 1985 |
| K & T Chaffey Enterprises Ltd | Real estate | 2017 |
| K & W Brick Haulage Limited | Transport & logistics | 1988 |
| K D Finance Limited | Financial services | 2016 |
| K D Group Developments Limited | Construction | 2024 |
| K D Group Holdings Limited | Financial services | 2016 |
| K D Group Limited | Financial services | 2015 |
| K D Group Management Limited | Real estate | 2024 |
| K D Group Properties 2 Limited | Real estate | 2026 |
| K D Group Properties Limited | Real estate | 2024 |
| K E Perfect Cleaning Ltd | Administrative & support | 2024 |
| K Gawronski Ltd | Construction | 2015 |
| K N Hakin Limited | Health & social care | 2002 |
| K R Architectural Design Ltd | Professional & scientific | 2021 |
| K W Fancy Limited | Construction | 2003 |
| K&M (South West) Limited | Construction | 2021 |
| K&R Allgood Limited | Financial services | 2022 |
| K.C.K. Company Services Limited | Professional & scientific | 1994 |
| K.N.R Scaffolding Limited | Construction | 2022 |
| K9 Care Services Limited | Other services | 2013 |
| K9 Mobile Security Limited | Administrative & support | 2009 |
| KA Health IT Services Ltd | Information & communication | 2019 |
| Kaamg Ltd | Information & communication | 2025 |
| Kaamim Limited | Health & social care | 2015 |
| Kairos Innovations Limited | Construction | 2008 |
| Kairos Kleos Limited | Professional & scientific | 2025 |
| Kakapo Limited | Real estate | 2024 |
| Kalwa General Building Ltd | Construction | 2019 |
| Kam-Rad Services Ltd | Construction | 2014 |
| Kamila Zak-Zieba & Krzysztof Zieba Ltd | Real estate | 2025 |
| Kanakanti Ltd | Health & social care | 2023 |
| Kanalife Ltd | Wholesale & retail | 2019 |
| Kandavan Limited | Manufacturing | 2020 |
| Kanon Metrics Ltd | Professional & scientific | 2026 |
| Kapree Property LLP | | 2025 |
| Karen Croft Ltd | Wholesale & retail | 2022 |
| Karl Hatcher Holdings Limited | Administrative & support | 2016 |
| Karman Estates Limited | Real estate | 2015 |
| Kasslee Solutions Ltd | Information & communication | 2023 |
| Katch Maintenance Limited | Construction | 2003 |
| Kate Sellick Ltd | Financial services | 2024 |
| Kate Walker Bridal Limited | Wholesale & retail | 2010 |
| Katie Corkill Decorating Ltd | Construction | 2023 |
| Katie Davis Limited | Financial services | 2022 |
| Katie Sims Collections Ltd | Arts & recreation | 2023 |
| Kaylight Ltd | Wholesale & retail | 2023 |
| Kbaksh LLP | | 2007 |
| KC Care Consultancy Ltd | Information & communication | 2021 |
| KC Holding Ltd | Administrative & support | 2007 |
| Kchurch Ltd | Financial services | 2024 |
| Keane Media Services Limited | Professional & scientific | 2006 |
| Kedvale Consultants Limited | Professional & scientific | 1998 |
| Keedwell (Scotland) Holdings Limited | Professional & scientific | 2015 |
| Keedwell (Scotland) Limited | Transport & logistics | 2015 |
| Keen Pathology Limited | Health & social care | 2010 |
| Keep Marriage Special Limited | Professional & scientific | 2011 |
| Keith Farmer Building Services Ltd | Construction | 2015 |
| Keith Martin Robinson Ltd | Extraterritorial | 2025 |
| Keith Summers Ltd | Agriculture & fishing | 2012 |
| Kelvin Rufus Ltd | Professional & scientific | 2002 |
| Kelvin White Driving School Ltd | Education | 2006 |
| Kelvin White Instructor Training Ltd | Education | 2013 |
| Kemi Oladapo Consulting Limited | Professional & scientific | 2015 |
| Kemony Limited | Health & social care | 2020 |
| Kempston Limited | Manufacturing | 1979 |
| KEN Gibbs (Honiton) Limited | Real estate | 1978 |
| KEN Jones Transport (Goldcliff) Limited | Transport & logistics | 1989 |
| KEN Magill & SON Limited | Construction | 2005 |
| Ken's Consulting Limited | Professional & scientific | 2025 |
| Kendot Limited | Professional & scientific | 2022 |
| Kenn Developments Limited | Construction | 2010 |
| Kennet Sign and Display Limited | Manufacturing | 2008 |
| Kensington Cameras Ltd | Construction | 2026 |
| Kernow Health East Limited | Health & social care | 2017 |
| KES Art Ltd | Manufacturing | 2023 |
| Kestrel Construction Ltd | Construction | 2020 |
| Ketchen Social Work Ltd | Health & social care | 2014 |
| Kevin Paul Builder Limited | Construction | 2014 |
| Kevin Shearn Family Law Practice Limited | Professional & scientific | 2014 |
| Kevs Cleaning Services Limited | Other services | 2005 |
| Key Funding Limited | Financial services | 2013 |
| Key Stage Tuition Ltd | Education | 2024 |
| Key Whizz Limited | Transport & logistics | 2023 |