| King & Co Financial Services Limited | Financial services | 2002 |
| King and Co Property Management Limited | Real estate | 2004 |
| King Brands Limited | Wholesale & retail | 2017 |
| King Industries Limited | Agriculture & fishing | 2008 |
| King Street (Desborough) Limited | Households | 1992 |
| Kingfisher Country Club Limited | Hospitality | 1995 |
| Kingfisher Partnerships Ltd | Construction | 2025 |
| Kingfix Auto Solutions Limited | Wholesale & retail | 2025 |
| Kingmaker Consultants Ltd | Professional & scientific | 2019 |
| Kingpin Consultancy Limited | Manufacturing | 1998 |
| Kings Heath Residents Association CIC | Information & communication | 2025 |
| Kings Road Grooming Lounge Limited | Other services | 2014 |
| Kingsbury Investment Holding Ltd | Real estate | 2022 |
| Kingsclean Limited | Administrative & support | 2023 |
| Kingsfield Leasing Limited | Wholesale & retail | 2011 |
| Kingshill Park Ltd | Real estate | 2021 |
| Kingsley Bathroom Plumbing & Heating Centre Limited | Wholesale & retail | 2008 |
| Kingsley Breakfast House Ltd | Hospitality | 2026 |
| Kingsley Builders Limited | Construction | 1987 |
| Kingsley Convenience Store Ltd | Wholesale & retail | 2022 |
| Kingsley Court (Rothwell) Limited | Households | 1988 |
| Kingsley Legal Consultancy Ltd | Professional & scientific | 2014 |
| Kingsley Local Limited | Wholesale & retail | 2019 |
| Kingsley Roofing Contractors Limited | Construction | 2023 |
| Kingsley Surveys Ltd | Professional & scientific | 2026 |
| Kingsmith Installations Limited | Manufacturing | 2010 |
| Kingsmith Steel Limited | Administrative & support | 2010 |
| Kingsthorpe Auto Body Shop Ltd | Wholesale & retail | 2026 |
| Kingsthorpe Bowling Club Limited(The) | Arts & recreation | 1926 |
| Kingsthorpe Construction & Refurbishment Ltd | Construction | 2014 |
| Kingsthorpe Construction Limited | Construction | 2011 |
| Kingsthorpe Golf Company Limited | Real estate | 1913 |
| Kingsthorpe House Management Limited | Households | 1982 |
| Kingsthorpe Konstruction Ltd | Construction | 2023 |
| Kingsthorpe Lasaan Limited | Hospitality | 2025 |
| Kingsthorpe Precision Engineering Limited | Professional & scientific | 2016 |
| Kingsthorpe Toning Tables Studio Ltd | Health & social care | 2020 |
| Kingston House (EG) Limited | Real estate | 2024 |
| Kingstone Construction Ltd | Construction | 2014 |
| Kingswell Construction Limited | Construction | 2026 |
| Kingswell Scaffolding LLP | | 2014 |
| Kingswood Global Business Limited | Financial services | 2004 |
| Kingswood Property Development and Management Ltd | Real estate | 2018 |
| Kingswood Sales & Lettings Limited | Real estate | 2009 |
| Kinisi Limited | Professional & scientific | 2013 |
| Kinje Limited | Professional & scientific | 2025 |
| Kinoulton Properties Limited | Real estate | 1998 |
| Kinsella Estates Limited | Construction | 2007 |
| Kinwith Limited | Real estate | 2023 |
| Kippari Ltd | Transport & logistics | 2019 |
| Kipper Property LLP | | 2007 |
| KIR Construction Limited | Construction | 2015 |
| Kiranveer Properties Ltd | Real estate | 2021 |
| Kiraya Limited | Administrative & support | 2019 |
| Kiri Properties Ltd | Real estate | 2021 |
| Kirkely Meadows Ltd | Hospitality | 2024 |
| Kirkholme Gardens Management Company Limited | Households | 2020 |
| Kirkland & Co Brickwork and Groundwork Ltd | Construction | 2025 |
| Kirkland Consultants Limited | Administrative & support | 2007 |
| Kirti Shah Limited | Health & social care | 2010 |
| KIS Coaches and Taxis Limited | Transport & logistics | 2002 |
| Kisel Service Ltd | Transport & logistics | 2021 |
| Kishen & Arti Ltd | Real estate | 2024 |
| Kisle Landscapes Ltd | Administrative & support | 2021 |
| Kislingbury Mill Maintenance Ltd | Households | 2021 |
| Kislingbury Properties Limited | Real estate | 2001 |
| Kiss E-Motion Ltd | Manufacturing | 2022 |
| Kist Rentals Ltd | Real estate | 2026 |
| KIT Quote Ltd | Information & communication | 2026 |
| Kitchenn Ltd | Manufacturing | 2019 |
| Kitchens for Less Ltd | Wholesale & retail | 2022 |
| Kitround Limited | Wholesale & retail | 2025 |
| KITROUND360 Limited | Information & communication | 2025 |
| KITS4CLOCKS Limited | Wholesale & retail | 2025 |
| Kitsis Ltd | Hospitality | 2019 |
| Kitson Estates Ltd | Real estate | 2024 |
| Kiziak Group Limited | Financial services | 2020 |
| Kizzle Autos Ltd | Wholesale & retail | 2016 |
| KJ Beauty Limited | Other services | 2025 |
| KJ Equine Angel Limited | Agriculture & fishing | 2011 |
| KJ Pickering Limited | Construction | 1997 |
| KJC Enterprise's Ltd | Hospitality | 2022 |
| KJK Lettings Limited | Real estate | 2021 |
| KJM Farm Consulting Ltd | Professional & scientific | 2024 |
| KJT Property Rentals Limited | Real estate | 2015 |
| KJW Group Limited | Financial services | 2017 |
| KJW Solutions Ltd | Professional & scientific | 2018 |
| KKE36OROU Limited | Public administration | 2025 |
| KKL Group Limited | Construction | 2021 |
| Kkslj Limited | Transport & logistics | 2025 |
| KL Drone Services Ltd | Information & communication | 2024 |
| KL IRD LLP | | 2023 |
| Klarion Herbal Limited | Wholesale & retail | 2024 |
| Klassik Kreations Ltd | Other services | 2019 |
| Kleandrive Repower UK Limited | Other services | 2026 |
| Kleenext Ltd | Construction | 2025 |
| Kleenify Solutions Ltd | Administrative & support | 2024 |
| Klement M Limited | Other services | 2012 |
| Klinghardt Education Limited | Health & social care | 2016 |
| KLL Consulting Limited | Other services | 2014 |