| Kavannagh Partnership UK Limited | Construction | 2017 |
| Kayak Records Ltd | Arts & recreation | 2022 |
| Kays Electrical Services Ltd | Construction | 2011 |
| Kbhr Limited | Administrative & support | 2021 |
| Kbuxton Properties Ltd | Construction | 2019 |
| KC Interior Solutions Ltd | Construction | 2019 |
| KCB Property Group Ltd | Real estate | 2021 |
| KCL Lettings Limited | Households | 2010 |
| KD G Brothers Limited | Hospitality | 2023 |
| KDD Projects Ltd | Construction | 2018 |
| KEA Housing Estates Limited | Real estate | 2025 |
| Keder Greenhouses Limited | Administrative & support | 2005 |
| Keely Julie Joanne Alison O’Leary Limited | Professional & scientific | 2022 |
| Keen Support Limited | Professional & scientific | 2025 |
| Keflavik Limited | Administrative & support | 2007 |
| KEG Services Ltd | Professional & scientific | 2026 |
| Kelbec Civils Limited | Construction | 2000 |
| Kelly Phasey Fitness Ltd | Wholesale & retail | 2018 |
| Kemdesign Ltd | Construction | 2024 |
| KEN Priest Fire Risk Assessments and Training Limited | Education | 2012 |
| Kenneth Morris Limited | Professional & scientific | 2007 |
| Kensington Films Limited | Professional & scientific | 2011 |
| Kenworth Business Services Limited | Real estate | 1999 |
| Kerb EZZ Wheel Refurbishment Ltd | Wholesale & retail | 2023 |
| Kev's Cars and Coaches Limited | Transport & logistics | 2002 |
| KEW Moving Pictures Limited | Information & communication | 2013 |
| Keynote Films Ltd | Information & communication | 2020 |
| Keys Farm Development Management Limited | Households | 2003 |
| Keyworth Car Sales Ltd | Wholesale & retail | 2022 |
| Keyworth Garages Midlands Ltd | Wholesale & retail | 2022 |
| KF Warwickshire Homes Ltd | Real estate | 2020 |
| Khela Real Estate Ltd | Real estate | 2022 |
| KHS Engineering Company Limited | Professional & scientific | 2006 |
| Khzif Ltd | Wholesale & retail | 2013 |
| Kibwe Tavares Limited | Information & communication | 2015 |
| Kidderminster Roofing Supplies Limited | Wholesale & retail | 2007 |
| Kids Physiotherapy Limited | Health & social care | 2011 |
| Kiki Property Flip Ltd | Real estate | 2024 |
| Killeen Executive Search Limited | Administrative & support | 2023 |
| Killer Lemon Limited | Arts & recreation | 2025 |
| Kinderminds Ltd | Wholesale & retail | 2024 |
| Kinetic People Development Limited | Professional & scientific | 2019 |
| King Edmund Square Management Limited | Real estate | 1992 |
| Kingdom Horse Community Interest Company | Agriculture & fishing | 2006 |
| Kingfisher Foam Products Limited | Wholesale & retail | 2008 |
| Kingfisher Rubber & Plastics Ltd | Manufacturing | 2009 |
| Kingston Morley Limited | Real estate | 2021 |
| Kingston Morley Properties Limited | Real estate | 2021 |
| Kinmel Lodge Limited | Health & social care | 2017 |
| Kinver Mount RTM Limited | Households | 2006 |
| KIT the Dog Trainer Ltd | Education | 2026 |
| Kitty Yoga Manchester Ltd | Agriculture & fishing | 2024 |
| Kiwi Design and Build Ltd | Construction | 2009 |
| Kiwi Design and Print Limited | Manufacturing | 1999 |
| Kiyani Digital Ltd | Administrative & support | 2003 |
| KJ Company Consultant Ltd | Professional & scientific | 2024 |
| KJA Consultancy Limited | Professional & scientific | 2012 |
| Kjap Consulting Ltd | Professional & scientific | 2018 |
| KJB Brickwork Ltd | Construction | 2008 |
| KJC by Karen Carney MBE Limited | Education | 2017 |
| Kjlj Ltd | Health & social care | 2025 |
| KLB Commercial Vehicle Repairs Ltd | Wholesale & retail | 2025 |
| KLD Consultancy Ltd | Financial services | 2025 |
| Klear Tech Consulting Ltd | Information & communication | 2025 |
| Klixup Ltd | Wholesale & retail | 2025 |
| KLM Maintenance Limited | Construction | 2011 |
| Kloff Ltd | Wholesale & retail | 2020 |
| KLT Childcare Ltd | Education | 2013 |
| Klwcoaching Ltd | Other services | 2025 |
| KM Bromsgrove Limited | Professional & scientific | 2008 |
| KMC Property Group Ltd | Real estate | 2026 |
| Kmrg Orthodontic Therapy Services Limited | Health & social care | 2017 |
| Knights Flooring Ltd | Other services | 2023 |
| Knights Inns Limited | Administrative & support | 2020 |
| Knights Project Solutions Ltd | Construction | 2025 |
| Knotweed Services (UK) Ltd | Administrative & support | 2012 |
| Knowles Vending Services Limited | Extraterritorial | 1972 |
| KNT Fleet Holdings Limited | Administrative & support | 2021 |
| KNT Investments 2 Limited | Administrative & support | 2020 |
| KNT Propco Limited | Real estate | 2023 |
| KO Removals and Maintenance Limited | Water & waste | 2023 |
| Kore Performance Ltd | Education | 2019 |
| Kotekar Limited | Health & social care | 2013 |
| KP Marsh Holdings Ltd | Financial services | 2024 |
| Kpcphysiotherapy Limited | Health & social care | 2017 |
| KPH Property Services Ltd | Construction | 2020 |
| KPK14 Limited | Information & communication | 2026 |
| Kresko Futures Limited | Professional & scientific | 2026 |
| Krowe Holdings Limited | Professional & scientific | 2019 |
| KSH Carpet & Flooring Ltd | Wholesale & retail | 2016 |
| Ksuk Environmental Limited | Administrative & support | 2026 |
| KSZ Trader Ltd | Wholesale & retail | 2023 |
| KTK Consulting Limited | Professional & scientific | 2018 |
| Kudos Property Developments Ltd | Construction | 2020 |
| Kylo Consulting Ltd | Professional & scientific | 2024 |
| L & C Food Market (Boston) Ltd | Wholesale & retail | 2019 |
| L & C Food Market (Rockhill) Ltd | Wholesale & retail | 2020 |
| L & C Food Market (Stourbridge) Ltd | Wholesale & retail | 2020 |
| L & C Food Market Ltd | Wholesale & retail | 2014 |
| L & S Lettings Limited | Real estate | 2014 |