| Kingscote Haulage Limited | Construction | 2020 |
| Kingscote Homes Ltd | Real estate | 2014 |
| Kingscote Post-Tensioning Limited | Construction | 2018 |
| Kingsland Holdings Limited | Health & social care | 2026 |
| Kingsway Facility Management (KFM) Ltd | Construction | 2025 |
| Kingsway Mezz Hold Co Limited | Financial services | 2014 |
| Kintek Holdings Ltd | Professional & scientific | 2020 |
| Kiray Care Consulting Ltd | Health & social care | 2019 |
| Kirkbray Limited | Health & social care | 2023 |
| Kirkby Central Group Limited | Professional & scientific | 1983 |
| Kish Gohil Payment Services Ltd | Administrative & support | 2018 |
| KIT & Kaboodle Designs Ltd | Manufacturing | 2015 |
| Kitchen Pictures Limited | Information & communication | 2019 |
| Kitchen Reflection Limited | Wholesale & retail | 2021 |
| Kitchenfindr Limited | Wholesale & retail | 2017 |
| Kite Live Ltd. | Professional & scientific | 2014 |
| Kitexa Limited | Administrative & support | 2018 |
| Kiyansh Goumet Limited | Hospitality | 2023 |
| Kizazi Solutions Limited | Financial services | 2024 |
| KJC Heating & Plumbing Ltd | Construction | 2021 |
| KKR Planning & Design Ltd | Professional & scientific | 2007 |
| KL Seabridge Ltd | Professional & scientific | 2010 |
| KL Townhouse Ltd | Wholesale & retail | 2026 |
| Klaasie Solutions Limited | Professional & scientific | 2025 |
| Kleinman Capital Ltd | Professional & scientific | 2014 |
| Klenam Services Limited | Health & social care | 2014 |
| Kliving Ltd | Real estate | 2021 |
| KLM Capital Ltd | Administrative & support | 2021 |
| KLM IT Solution Limited | Information & communication | 2014 |
| KLS Digital Solutions Limited | Information & communication | 2026 |
| Klva Investments Ltd | Financial services | 2019 |
| Klyvia Ltd | Wholesale & retail | 2025 |
| Kmedro Limited | Real estate | 2025 |
| Kmjr Holdco Limited | Financial services | 2025 |
| KMS Holdings Limited | Professional & scientific | 2007 |
| Kmsm Masterson Limited | Real estate | 2006 |
| KMW Consulting Limited | Information & communication | 2007 |
| Knightbridge Productions Limited | Information & communication | 2024 |
| Knightrate Investments 12 Ltd | Real estate | 2018 |
| Knightrate Limited | Information & communication | 2014 |
| Knights 1966 Limited | Real estate | 2017 |
| Knights Associates Ltd | Wholesale & retail | 2015 |
| Knights Court (N11) RTM Company Limited | Households | 2019 |
| Knights Court and Kennedy Court (Bushey) Residents Association Limited | Households | 1989 |
| Knightsbridge PR Limited | Information & communication | 2021 |
| Knill & Company Legal Services Limited | Professional & scientific | 2011 |
| KNM Transport Ltd | Administrative & support | 2025 |
| Known Publishing Ltd | Information & communication | 2019 |
| KNZ Property Limited | Real estate | 2024 |
| Knza Ltd | Information & communication | 2024 |
| Koala Tea Cleaning Services Limited | Administrative & support | 2024 |
| Kogs Medical Consultancy Limited | Professional & scientific | 2018 |
| Kogs Property Ltd | Real estate | 2024 |
| Koguk Ltd | Administrative & support | 2019 |
| Kohele Limited | Information & communication | 2009 |
| Kojin Limited | Real estate | 2014 |
| Kokomo Jewellery Design Ltd | Administrative & support | 2019 |
| Kokroko Wings Ltd | Hospitality | 2024 |
| Kokul Services Limited | Wholesale & retail | 2018 |
| Kolam Group Ltd | Financial services | 2025 |
| Koma Structural Engineers Ltd | Construction | 2013 |
| Konaku Limited | Hospitality | 2026 |
| Konceptmyart Limited | Arts & recreation | 2025 |
| Konect International Ltd | Professional & scientific | 2014 |
| Konton ZEN Limited | Manufacturing | 2019 |
| Koocx Limited | Health & social care | 2026 |
| Koru (Holdings) Limited | Professional & scientific | 2014 |
| Koru Chip Company Limited | Administrative & support | 2014 |
| Koru Services Limited | Administrative & support | 2015 |
| Kosher Foods Limited | Wholesale & retail | 2014 |
| Koshernet Limited | Wholesale & retail | 2012 |
| Kosmo SKC Ltd | Arts & recreation | 2021 |
| Kotrago Limited | Extraterritorial | 1952 |
| KP Vision Ltd | Financial services | 2017 |
| Kreative Pink Ltd | Professional & scientific | 2015 |
| Krestmore Construction Limited | Construction | 2022 |
| KRH Capital Group Limited | Professional & scientific | 2025 |
| Krishna Limited | Real estate | 2011 |
| Kristalize Limited | Financial services | 2024 |
| Krols (UK) Limited | Hospitality | 2010 |
| Kronos and Rhea Ltd | Wholesale & retail | 2020 |
| KRS Bright Limited | Health & social care | 2021 |
| KS Building & Construction Group Ltd | Construction | 2023 |
| KS Tax Advisors Limited | Professional & scientific | 2026 |
| KSE Entities Limited | Transport & logistics | 2018 |
| Ksneath Ltd | Health & social care | 2013 |
| KSS Estates Ltd | Real estate | 2021 |
| Ksvr Limited | Real estate | 2023 |
| Kumar & Brown Consultants Limited | Information & communication | 2009 |
| Kumitech Limited | Information & communication | 2023 |
| Kumquat Productions Limited | Information & communication | 2015 |
| Kutum Limited | Real estate | 2024 |
| KVI Chopstix Ltd. | Hospitality | 2011 |
| KWA Ventures Limited | Real estate | 2015 |
| KWL Insightful Analytics Ltd | Financial services | 2024 |
| Kyle Bubbly Limited | Arts & recreation | 2012 |
| Kyng Consultants Limited | Wholesale & retail | 2008 |
| Kyou Medical Ltd | Health & social care | 2023 |
| L & C Associates LLP | | 2015 |
| L & C Associates Properties Ltd | Real estate | 2025 |