| Kalsi Bedrooms Ltd | Manufacturing | 2023 |
| Kalsi Empire Ltd | Financial services | 2023 |
| Kalsi Interiors Ltd | Manufacturing | 2023 |
| Kalsi Kitchens & Bedrooms Ltd | Manufacturing | 2019 |
| Kalsi Kitchens Limited | Extraterritorial | 2023 |
| Kalsi Property Developments Ltd | Real estate | 2023 |
| Kalyssia Properties Ltd | Construction | 2020 |
| Kandy Girl Limited | Other services | 2017 |
| Kanengisser Limited | Real estate | 2021 |
| Kappa Pharmaceuticals Limited | Professional & scientific | 1987 |
| Kara Hairstylist Ltd | Other services | 2023 |
| Karamime Limited | | 1982 |
| Karez SI Ltd | Wholesale & retail | 2025 |
| Karinthia Heights Ltd | Health & social care | 2026 |
| Karios & SON Limited | Hospitality | 2018 |
| Karl Brennan Driving Services Limited | Administrative & support | 2014 |
| Karl Frew Ltd | Other services | 2011 |
| Karma (Homes) Limited | Construction | 2006 |
| Karma Homes Management Ltd | Real estate | 2009 |
| Kasaimoto Limited | Manufacturing | 2018 |
| KAT Capital Limited | Professional & scientific | 2015 |
| Kats Tattees Ltd | Hospitality | 2025 |
| Kaulsi Holdings Ltd | Real estate | 2025 |
| Kavanagh's Decorating & Design Limited | Construction | 2025 |
| KAY ESS Developments Ltd | Real estate | 2026 |
| KAY Leslie Consultancy Ltd | Professional & scientific | 2019 |
| KAY Property Development Ltd | Households | 2015 |
| KAY Property Ltd | Real estate | 2026 |
| Kay&Ess Ltd | Real estate | 2026 |
| Kayess Limited | Health & social care | 2015 |
| Kaykayjay Ltd | Real estate | 2018 |
| Kazi Space Ltd | Construction | 2024 |
| KB Opticians Limited | Real estate | 1997 |
| KBB & HR Ltd | Transport & logistics | 2020 |
| KC Quality Solutions Ltd | Professional & scientific | 2010 |
| KC Sdesign Ltd | Manufacturing | 2026 |
| KD Engineering Limited | Professional & scientific | 2022 |
| KD Global Ltd | Hospitality | 2025 |
| KD Models Limited | Wholesale & retail | 2009 |
| KDC Heating Ltd | Construction | 2026 |
| Kddk Limited | Arts & recreation | 2014 |
| Kdivision Limited | Professional & scientific | 2017 |
| KDM Fisheries Limited | Hospitality | 2026 |
| Keane Konsulting Limited | Information & communication | 2007 |
| Keats Coffee Houses Limited | Hospitality | 2019 |
| Keen Group Holdings Ltd | Real estate | 2023 |
| KEF Limited | Real estate | 2025 |
| Keiran James Construction Ltd | Construction | 2022 |
| Kelbake Limited | Real estate | 1996 |
| Kellas Consulting Ltd | Professional & scientific | 2025 |
| Kellaways (Funeral Service) Limited | Extraterritorial | 1973 |
| Kells Property Management Ltd | Real estate | 2026 |
| Kelly Hunter (UK) Ltd | Wholesale & retail | 2021 |
| Kellys Groundwork Ltd | Construction | 2025 |
| Kelpoint Limited | Real estate | 2005 |
| Kemberton Holdings Ltd | Real estate | 2019 |
| Kemberton Services Shropshire Limited | Extraterritorial | 2010 |
| Kempson Construction Ltd | Construction | 2018 |
| Kempster Valves Limited | Manufacturing | 2021 |
| KEN Gregory & Sons Limited | Extraterritorial | 2003 |
| KEN IM Limited | Information & communication | 2018 |
| Kennelly Solutions Ltd | Construction | 2015 |
| Kenny Civils Limited | Construction | 2024 |
| Kensington Services Limited | Financial services | 2001 |
| Kent Funeral Supplies Limited | Extraterritorial | 1963 |
| Kenyon Air Transportation Limited | Extraterritorial | 1975 |
| Kenyon Emergency Services Limited | Extraterritorial | 1986 |
| Kenyon Repatriation Ltd | Extraterritorial | 1993 |
| Kenyon Securities Limited | Extraterritorial | 1976 |
| Kenyons Funeral Directors Limited | Extraterritorial | 2000 |
| Keratech Laboratories Limited | Other services | 2018 |
| Kerbed 'N' Refurbed Ltd | Administrative & support | 2017 |
| Kerimet Technology Limited | Manufacturing | 2022 |
| Kerlow Property Limited | Real estate | 2018 |
| Key 2 Space Limited | Real estate | 2014 |
| Key Architectural Design Limited | Professional & scientific | 2013 |
| Key Insight Marketing & Consulting Team Limited | Administrative & support | 2025 |
| Key Scaffold Ltd | Construction | 2013 |
| Keychain Property Ltd | Real estate | 2017 |
| Keyhill Developments Limited | Construction | 2022 |
| Keykeys Properties Limited | Real estate | 2020 |
| Keystone Accountants Limited | Professional & scientific | 2021 |
| Keystone Business Advisers Limited | Professional & scientific | 1983 |
| Keystone Financial Solutions Limited | Professional & scientific | 2018 |
| Keystone Partners Corporate Finance LLP | | 2017 |
| Keywise Ltd | Transport & logistics | 2017 |
| Kfada Ventures Ltd | Wholesale & retail | 2025 |
| KH Marketing Consultancy Limited | Professional & scientific | 2010 |
| Khalemed Ltd | Administrative & support | 2022 |
| Khalsa Travel Home Ltd | Administrative & support | 2023 |
| Kharabanda Properties Limited | Financial services | 2022 |
| Kheera Ltd | Wholesale & retail | 2025 |
| Khosla Ltd | Professional & scientific | 2002 |
| Khwan's Warren Ltd | Real estate | 2025 |
| Kidderminster Care Limited | Health & social care | 2000 |
| Kidlington Barbers Ltd | Other services | 2018 |
| Kids | Health & social care | 1977 |
| Kids Trading Company Limited | Extraterritorial | 1998 |
| Kidsactive | Extraterritorial | 1982 |
| Kidslingo Ltd | Education | 2015 |