| Keeley Wellbeing Ltd | Public administration | 2023 |
| Keep IT Rugby CIC | Wholesale & retail | 2024 |
| Keerat Rugby Auto Tyres Ltd | Wholesale & retail | 2026 |
| Keerthika Limited | Wholesale & retail | 2018 |
| Kejayaan Consulting Ltd | Information & communication | 2014 |
| Kelleher Project Services Ltd | Professional & scientific | 2012 |
| Kelpie Business Services Ltd | Professional & scientific | 2017 |
| Kemb Bookkeeping & Accountancy Ltd | Professional & scientific | 2022 |
| Kember Property Partnership Limited | Real estate | 2024 |
| Kenidi Ltd | Transport & logistics | 2018 |
| Kenilworth and District Agricultural Society | Professional & scientific | 1998 |
| Kenmat Care Limited | Health & social care | 2019 |
| Kennedy Johnson Associates Ltd | Professional & scientific | 2019 |
| Kenya Auto Exports Ltd. | Wholesale & retail | 2011 |
| Kenzaa Ltd | Hospitality | 2022 |
| Kerruish Creative Ltd | Professional & scientific | 2025 |
| Kerry Suntime Company Limited(The) | Construction | 1983 |
| Kevin Green Bespoke Joinery and Building Services Limited | Construction | 2011 |
| Keydrive Holdings Ltd | Wholesale & retail | 2025 |
| Keyzume Services Limited | Health & social care | 2024 |
| Kezang Limited | Manufacturing | 2018 |
| Kezy Care Services Limited | Health & social care | 2015 |
| KH Collective Ltd | Professional & scientific | 2025 |
| Khusi General Stores Limited | Wholesale & retail | 2005 |
| KIA Adventures Ltd | Transport & logistics | 2026 |
| Kies Limited | Real estate | 1989 |
| KIG (Nottm) Limited | Education | 2012 |
| Kigs Logistics Ltd | Transport & logistics | 2022 |
| Kikaira Limited | Health & social care | 2024 |
| Kilbey Catering Limited | Hospitality | 2009 |
| Kiln Farm Club Investment Limited | Administrative & support | 2010 |
| KIMBOSLICE1 Limited | Extraterritorial | 2024 |
| Kindlecone Ltd | Extraterritorial | 2011 |
| King Music Publishing Co.Limited | Information & communication | 1965 |
| Kingsway Electrical Distributors Limited | Wholesale & retail | 2016 |
| Kinzol Limited | Extraterritorial | 2018 |
| Kiratrans Limited | Transport & logistics | 2018 |
| Kirby Court Management Company Limited | Households | 2004 |
| Kirila Trans Ltd | Transport & logistics | 2024 |
| Kiri’ Kitchen Ltd | Hospitality | 2024 |
| Kirpa Properties COV Ltd | Real estate | 2025 |
| Kirsch Securities Limited | Real estate | 1962 |
| Kirwin & Simpson (Properties) Limited | Extraterritorial | 1953 |
| Kirwin and Simpson (International) Limited | Real estate | 1973 |
| Kiss Curl Limited | Other services | 2014 |
| Kiss My Brand Limited | Extraterritorial | 2024 |
| Kita Group Ltd | Real estate | 2026 |
| KITA5 Limited | Health & social care | 2023 |
| Kitchensuite Ltd. | Wholesale & retail | 2013 |
| Kitob Premium Limited | Health & social care | 2025 |
| Kits Academy Limited | Arts & recreation | 2017 |
| Kiwi Gyms Ltd | Wholesale & retail | 2023 |
| KJ Transport (Midlands) Ltd | Transport & logistics | 2016 |
| KJL UK Property Management Limited | Real estate | 2025 |
| KKM Mortgages Limited | Financial services | 2025 |
| KKW Solution Ltd | Administrative & support | 2017 |
| Klickers Hairdressing LLP | | 2022 |
| Klickers Limited | Other services | 2011 |
| KM Cladding Ltd | Construction | 2024 |
| KM User Researcher Limited | Administrative & support | 2013 |
| Kmcee Style Ltd | Wholesale & retail | 2022 |
| KMK Medics Ltd | Health & social care | 2017 |
| KMN Medicare Limited | Health & social care | 2022 |
| KMR Transport (Warwickshire) Ltd | Transport & logistics | 2025 |
| KMS Business Solutions Ltd | Professional & scientific | 2005 |
| KN Lettings Limited | Real estate | 2020 |
| KNH Rugby Properties Limited | Real estate | 2026 |
| Knightlow Healthcare Services Limited | Education | 2012 |
| Knights Inns Holdings Limited | Hospitality | 2021 |
| Knights Surfacing Ltd | Construction | 2025 |
| Knott Brothers Limited | Construction | 2017 |
| Knotyouraveragecarpentry Ltd | Manufacturing | 2026 |
| Know IT ALL Ltd | Manufacturing | 2021 |
| KNOWN4 AI Ltd | Information & communication | 2026 |
| Kolaa Limited | Transport & logistics | 2012 |
| Kona Properties Ltd | Real estate | 2021 |
| Konekt Living Ltd | Hospitality | 2025 |
| Konnectum Limited | Administrative & support | 2023 |
| Kooner Family Holdings UK Ltd | Real estate | 2025 |
| Kooner Housing Ltd | Real estate | 2022 |
| Kopilot Ltd | Information & communication | 2025 |
| KOR Ventures Limited | Wholesale & retail | 2016 |
| Kora Carpets and Flooring Ltd | Construction | 2023 |
| Kornel & Partners Ltd | Transport & logistics | 2019 |
| Korvin HD Limited | Transport & logistics | 2016 |
| Koukakis Enterprises UK Ltd | Professional & scientific | 2025 |
| Kovacs Enterprises Ltd | Real estate | 2022 |
| Kowa Organics Ltd | Wholesale & retail | 2020 |
| KP Homes Leicester Ltd | Real estate | 2026 |
| KP IT Solutions Limited | Extraterritorial | 2016 |
| KP Quality Consultancy Ltd | Extraterritorial | 2014 |
| KP Tech Solutions Ltd | Professional & scientific | 2026 |
| KPB Monarch Limited | Professional & scientific | 2010 |
| KPI & SON Group Ltd | Wholesale & retail | 2025 |
| KR 79 Logistics Limited | Transport & logistics | 2017 |
| KR33 Ltd | Health & social care | 2021 |
| Kreya QA Services Ltd | Information & communication | 2022 |
| KRF. UK. Ltd. | Wholesale & retail | 1992 |
| Kris-Rider Ltd | Construction | 2018 |
| Krishan G Limited | Real estate | 2022 |