| Keto Samples Limited | Other services | 2021 |
| Keuka Limited | Real estate | 2019 |
| Keurbooms Limited | Wholesale & retail | 2004 |
| Kevin Day Aircraft Interiors Ltd | Manufacturing | 2018 |
| Kevs Discount Spares Ltd | Administrative & support | 2014 |
| Kevser Limited | Hospitality | 2020 |
| KEW Apartments (Peymans) Ltd | Administrative & support | 2015 |
| KEW Bridge Freehold Limited | Households | 2025 |
| KEW Investments Ltd | Manufacturing | 1997 |
| Kewlan Management Services Limited | Real estate | 1979 |
| Kewley Legal Services Ltd | Professional & scientific | 2014 |
| Key and Flowers Limited | Financial services | 2023 |
| Keyflock Digital Ltd | Information & communication | 2026 |
| Keyframe Creative & Advertising Ltd | Professional & scientific | 2023 |
| Keymer Cavendish Limited | Administrative & support | 2003 |
| Keynote PR Limited | Professional & scientific | 2006 |
| Keyray Group Limited | Extraterritorial | 2023 |
| Keystone Armis Limited | Professional & scientific | 2026 |
| Keyvia PM Limited | Real estate | 2025 |
| KF Interiors Limited | Construction | 2025 |
| KF Warehouse Ltd | Wholesale & retail | 2022 |
| KFP Cambridge Limited | Financial services | 2015 |
| Kg&Mg Investment Company | Financial services | 2026 |
| KH Casa Limited | Hospitality | 2025 |
| KH Construction (Cambridge) Limited | Construction | 2018 |
| KH Properties (Cambridge) Limited | Real estate | 2018 |
| Khaja Limited | Hospitality | 2024 |
| Khalid Durrani Motors Ltd | Wholesale & retail | 2023 |
| Khan Property (Cambridge) Limited | Real estate | 2017 |
| Khandoba Limited | Health & social care | 2016 |
| Khanmac Ltd | Construction | 2022 |
| Khans Garments Limited | Wholesale & retail | 2019 |
| Kheper B Limited | Education | 2026 |
| Kheper C Community Interest Company | Education | 2025 |
| Kherion Technology Limited | Professional & scientific | 2003 |
| Khin Limited | Health & social care | 2019 |
| KHRM1968 Limited | Information & communication | 2012 |
| KHS International Ltd | Wholesale & retail | 2024 |
| KHS Pharma Ltd | Wholesale & retail | 2023 |
| Khudoynazar Ltd | Construction | 2024 |
| Khushi Living Limited | Extraterritorial | 2017 |
| Kick-Point International Limited | Financial services | 2025 |
| Kidman Auto Electrical Limited | Wholesale & retail | 2014 |
| Kidman Build Limited | Construction | 2016 |
| Kidman Holdings Limited | Administrative & support | 2026 |
| Kidnetics Ltd | Manufacturing | 2024 |
| Kids Choice Ltd | Health & social care | 2018 |
| Kiernan Group Ltd | Hospitality | 2023 |
| Kieszonka Company Ltd | Manufacturing | 2025 |
| Kigee Hoist &Crane Ltd | Extraterritorial | 2019 |
| Kigen (Services) Limited | Information & communication | 2025 |
| Kigen (UK) Limited | Information & communication | 2020 |
| Kigezi International School of Medicine Ltd | | 1996 |
| Kiipling Ltd | Information & communication | 2025 |
| Kilana Limited | Households | 2001 |
| Kilbrogan Consulting Ltd | Professional & scientific | 2025 |
| Killiney Capital Ltd | Professional & scientific | 2021 |
| Kilmagner Ltd | Construction | 2023 |
| Kilncourt Residents Management Company Limited | Real estate | 2009 |
| KIM Tech Holdings Limited | Professional & scientific | 2017 |
| KIM Technologies Limited | Information & communication | 2015 |
| Kimchili Ltd | Hospitality | 2022 |
| Kimmiter Consulting Ltd | Professional & scientific | 2020 |
| Kimtai Limited | Wholesale & retail | 2024 |
| KIN Consulting Ltd | Professional & scientific | 2018 |
| Kincom Industries Co., Ltd | Extraterritorial | 2020 |
| Kind Earth Designs for ALL Limited | Health & social care | 2021 |
| Kind Sky Co., Ltd | Extraterritorial | 2019 |
| Kind Wellbeing Ltd | Wholesale & retail | 2025 |
| Kindersley Crescent Property Management Company Limited | Real estate | 2006 |
| Kindred Soul Ltd | Professional & scientific | 2018 |
| King's College Cambridge Developments Limited | Construction | 2000 |
| King's College Cambridge Enterprises Limited | Wholesale & retail | 1979 |
| King's College School, Cambridge | Education | 2021 |
| King's Keep (Cambridge) Management Company Limited | Households | 2010 |
| Kingdom Cocktails and Bartenders Ltd | Wholesale & retail | 2024 |
| Kingdom Education Group (UK) Limited | Education | 2012 |
| Kingfisher Court Cambridge Management Company Limited | Households | 2000 |
| Kingfisher Innovation Ltd | Administrative & support | 2025 |
| Kingfisher Labs Ltd | Information & communication | 2020 |
| Kingfisher Manufacturing Ltd | Manufacturing | 2020 |
| Kingfisher Properties Cambridge Limited | Hospitality | 2014 |
| Kings Catering Equipment Ltd | Wholesale & retail | 2025 |
| Kings Court (Ashby) Management Company Limited | Households | 2006 |
| Kings Court (Surrey) Management Company Limited | Households | 2007 |
| Kings English Cambridge Limited | Education | 2019 |
| Kings Lynn Mobile Home Park Limited | Real estate | 2004 |
| Kingsbrook Estate Management Company Limited | Households | 2016 |
| Kingsland Osteopaths Ltd | Health & social care | 2009 |
| Kingsley Block Management Company Limited | Real estate | 2020 |
| Kingsman Real Estate Cambridge Ltd | Real estate | 2024 |
| Kingsmoat Limited | Information & communication | 2021 |
| Kingston Agricultural Services Limited | | 1977 |
| Kingston Electrical Limited | Construction | 2014 |
| Kingston Property Partners Ltd | Real estate | 2025 |
| Kingston Wireless Ltd | Information & communication | 2013 |
| Kingston Wood LLP | | 2014 |
| Kingsway Solar Community Action CIC | Other services | 2026 |
| Kingswood (Cambourne) Management Company Limited | Households | 2002 |
| Kingtech (KTC) Machinery Group Co., Ltd | Extraterritorial | 2010 |