| Kingsmead Financial Planning Ltd | Financial services | 2013 |
| Kingswood Consultancy Services Ltd | Real estate | 2021 |
| Kingswood Consulting HSC Limited | Health & social care | 2024 |
| Kingswood Equestrian Ltd | Agriculture & fishing | 2025 |
| Kingswood Inks & Coatings (UK) Limited | Wholesale & retail | 2009 |
| Kinzig Limited | Financial services | 2024 |
| Kiop Ltd | Professional & scientific | 2009 |
| Kirkwood Mclean Projects Limited | Real estate | 2020 |
| Kirwan Holdings Limited | Financial services | 2025 |
| Kirwan Properties Limited | Real estate | 2025 |
| Kiss Media Inc Limited | Professional & scientific | 2020 |
| Kitchen 688 Limited | Hospitality | 2026 |
| Kite Sail Ltd | Professional & scientific | 2021 |
| Kitmarks Limited | Professional & scientific | 2025 |
| Kiwi Fit Couriers Ltd | Transport & logistics | 2024 |
| Kizito Engineering Limited | Professional & scientific | 2025 |
| KJ UK Retail Ltd | Wholesale & retail | 2025 |
| KJC Creative Ltd. | Professional & scientific | 2013 |
| KJC Flooring Limited | Construction | 2007 |
| KK Architects Limited | Professional & scientific | 2012 |
| KK Metro Properties Ltd | Real estate | 2024 |
| Kkabul Ltd | Hospitality | 2025 |
| Kkboss Ltd | Wholesale & retail | 2026 |
| KKM Construction Limited | Professional & scientific | 2024 |
| Klean N Go Ltd | Administrative & support | 2024 |
| Kleon Motors Ltd | Other services | 2022 |
| Klipspringer Consulting Limited | Construction | 2020 |
| Klovva Limited | Construction | 2007 |
| KM Auto Services Ltd | Wholesale & retail | 2025 |
| KM Network Solutions Ltd | Other services | 2015 |
| KM Signs and Graphics Ltd | Manufacturing | 2020 |
| Kmautoparts Ltd | Wholesale & retail | 2021 |
| KML Access Ltd | Construction | 2025 |
| Kmtp Limited | Professional & scientific | 2022 |
| Knightliner Executive Travel Ltd | Transport & logistics | 2018 |
| Knightsbridge Contracts Limited | Extraterritorial | 2023 |
| Knightscote (Bodicote) Management Company Limited | Real estate | 2014 |
| Knoldhill Limited | Professional & scientific | 2017 |
| Knotline Marine Ltd | Financial services | 2025 |
| Know Your Area Limited | Information & communication | 2024 |
| Knowledgekeys Limited | Education | 2024 |
| Knox Partners Ltd | Real estate | 2016 |
| KNS Heating and Plumbing Ltd | Construction | 2025 |
| Ko-Sheen Contract Cleaning Ltd | Administrative & support | 2002 |
| Kobbera Ltd | Financial services | 2014 |
| Kojo Nutrition Ltd | Health & social care | 2026 |
| Kolasa Transport Ltd | Transport & logistics | 2016 |
| Komo Drylining Ltd | Construction | 2026 |
| Komorebi Works Limited | Professional & scientific | 2021 |
| Kongca Catering Limited | Hospitality | 2025 |
| Kongur Ltd | Arts & recreation | 2012 |
| Kool Touch Limited | Energy | 2014 |
| Kool Vent Ltd | Construction | 2019 |
| Kora Consulting Ltd | Information & communication | 2020 |
| Koru Glass Limited | Construction | 2013 |
| Kothu Kadai Ltd | Hospitality | 2020 |
| Kovo Heat Ltd | Construction | 2023 |
| Kpeb Limited | Health & social care | 2023 |
| Kpld Ltd | Information & communication | 2018 |
| KPM Properties Limited | Real estate | 2010 |
| Kpsp Services Limited | Transport & logistics | 2009 |
| KQL Ltd | Information & communication | 2011 |
| Kratos Solutions Ltd | Professional & scientific | 2025 |
| Krave Kebab & Curry Ltd | Hospitality | 2023 |
| Krics Party Wall Surveyors Ltd | Professional & scientific | 2023 |
| Krisar SYS Limited | Information & communication | 2015 |
| Krisardeliveryservices Ltd | Transport & logistics | 2025 |
| Krishnasai Limited | Health & social care | 2023 |
| Krisplussound Ltd | Arts & recreation | 2024 |
| Kriss Care Recruitment Ltd | Administrative & support | 2024 |
| Kriss Consults Ltd | Information & communication | 2020 |
| KRM3 Ltd. | Health & social care | 2015 |
| Krmk Services Ltd | Information & communication | 2025 |
| Krrsg Consulting Ltd | Information & communication | 2018 |
| Krytom Limited | Professional & scientific | 2005 |
| KS Builders Direct Limited | Construction | 2003 |
| KSG Executive Search Ltd | Professional & scientific | 2009 |
| KT Beauty Lounge Aylesbury Limited | Other services | 2025 |
| KTA Civil Engineering Ltd | Construction | 2024 |
| Ktrm Care Ltd | Health & social care | 2017 |
| KTT Services Limited | Construction | 1997 |
| Kubus Plus Ltd | Wholesale & retail | 2025 |
| Kuester (Medical) Limited | Professional & scientific | 2009 |
| Kukino Ltd | Information & communication | 2008 |
| Kulveen Ltd | Wholesale & retail | 2026 |
| Kumusha Luxury Travel Ltd | Administrative & support | 2019 |
| Kumusha-Ekhaya Ventures Ltd | Information & communication | 2020 |
| Kunda Ltd | Professional & scientific | 2024 |
| Kunene Consulting Limited | Information & communication | 2025 |
| KUP Investments Ltd | Real estate | 2022 |
| Kv&M Limited | Wholesale & retail | 2023 |
| KVA Design Limited | Extraterritorial | 2008 |
| KVA Health Limited | Extraterritorial | 2018 |
| Kvas Retail Ltd | Wholesale & retail | 2025 |
| KVR Technology Solutions Ltd | Information & communication | 2024 |
| KW Architectural Limited | Professional & scientific | 2022 |
| KW24 Consulting Ltd | Professional & scientific | 2025 |
| Kylan Food & Wine Ltd | Wholesale & retail | 2024 |
| Kylie Downie Ltd | Hospitality | 2023 |
| Kylie Limited | Health & social care | 2019 |