| King David Tyres Limited | Wholesale & retail | 1975 |
| King of the Castles Limited | Arts & recreation | 2022 |
| King Scaffolding Limited | Construction | 1992 |
| Kingdom Partners Chambers Limited | Professional & scientific | 2021 |
| Kingfisher Treasure Seekers Ltd | Wholesale & retail | 2012 |
| Kingford Developments Limited | Construction | 2026 |
| Kingford Homes Limited | Construction | 2026 |
| Kingford Property Limited | Real estate | 2026 |
| Kingleymedia Ltd | Professional & scientific | 2026 |
| Kings Head Inn Birdwood LLP | | 2014 |
| Kingsbarton Theatre (1999) Limited | Arts & recreation | 1999 |
| Kingscott DIX Limited | Professional & scientific | 2010 |
| Kingsdown Ground Maintenance Limited | Administrative & support | 2019 |
| Kingshood Support Ltd | Health & social care | 2020 |
| Kingsley Welding Alloys Limited | Manufacturing | 2002 |
| Kingsthorne Limited | Manufacturing | 2018 |
| Kingsway Cache Limited | Real estate | 2006 |
| Kingsway Carpentry and Tiling Limited | Construction | 2024 |
| Kingsway Peri Peri Ltd | Hospitality | 2019 |
| Kingsweir Construction Services Ltd | Construction | 2015 |
| Kinja Quality Foods Ltd | Wholesale & retail | 2020 |
| Kirby and Knott Financial Planning Ltd | Financial services | 2018 |
| Kirby Prosthetics Studio Limited | Manufacturing | 2015 |
| Kirilini Limited | Wholesale & retail | 2025 |
| Kirsty Jayne Ltd | Hospitality | 2023 |
| KIS Information Services Limited | Information & communication | 2001 |
| Kisses at Christmas Ltd | Wholesale & retail | 2023 |
| Kissoon Investments Ltd | Real estate | 2024 |
| KIT Coaching Limited | Other services | 2025 |
| KIT Free Software 2024 Ltd | Information & communication | 2024 |
| Kitt Construction Limited | Construction | 2016 |
| Kiwi Motion Ltd | Wholesale & retail | 2023 |
| Kizelbach Ltd | Transport & logistics | 2018 |
| KJ Parry Electrical Contractors Ltd | Construction | 2003 |
| KJM Holdings Limited | Financial services | 2019 |
| KKB Solutions Limited | Wholesale & retail | 2025 |
| KKM Motors Ltd | Wholesale & retail | 2025 |
| KKZ Property UK Ltd | Real estate | 2026 |
| Klas Weddings Limited | Information & communication | 2025 |
| KLC Automall Ltd | Wholesale & retail | 2025 |
| Klean Eats Ltd | Hospitality | 2024 |
| Klingfilms Ltd | Extraterritorial | 2012 |
| Klingrin Ltd | Administrative & support | 2025 |
| Klotho Holdings Limited | Financial services | 2025 |
| KM Fitness & Fitness Entertainment Ltd | Arts & recreation | 2021 |
| Kmax Care Ltd | Professional & scientific | 2025 |
| KMG Motors Ltd | Wholesale & retail | 2021 |
| KMJ Property Maintenance Limited | Construction | 2003 |
| KML Developments Ltd | Construction | 2020 |
| KMO Ltd | Information & communication | 2019 |
| Knight & Co UK Ltd | Administrative & support | 2019 |
| Knight White Plumbing & Heating (Cheltenham) Ltd | Construction | 2026 |
| Knight White Plumbing & Heating LLP | | 2025 |
| Knight Window and Gutter Cleaning Ltd | Administrative & support | 2023 |
| Knights Essential Ltd | Information & communication | 2023 |
| Knights Touch Ltd | Construction | 2018 |
| Knowriskmarket UK Ltd | Information & communication | 2021 |
| Knowriskop UK Ltd | Information & communication | 2021 |
| KOA Solutions Ltd | Information & communication | 2016 |
| Koality Catering Services Limited | Hospitality | 2024 |
| Koco Bloom Holdings Limited | Financial services | 2025 |
| Koco Bloom Limited | Other services | 2025 |
| Kody Morgan Ltd | Construction | 2024 |
| Kolmad Property Limited | Real estate | 2020 |
| Kolmad Services Limited | Other services | 2011 |
| Komb Properties Ltd | Real estate | 2021 |
| Konesh & Co Ltd | Hospitality | 2018 |
| Konig Tyres Limited | Manufacturing | 2013 |
| Konstruct Klean Ltd | Construction | 2024 |
| Koottaan Cardiff Ltd | Manufacturing | 2023 |
| Koottaan Taunton Ltd | Wholesale & retail | 2021 |
| Kopernicus Limited | Real estate | 2025 |
| Koretek Limited | Professional & scientific | 2022 |
| Kosmic Bathrooms Ltd | Construction | 2021 |
| Kostas Trans Ltd | Transport & logistics | 2015 |
| Kovanchi Ltd | Hospitality | 2025 |
| Kovox Ltd | Professional & scientific | 2025 |
| Kovret Global Trading Limited | Wholesale & retail | 2026 |
| KPH Logistics Solutions Limited | Professional & scientific | 2019 |
| KPP Ltd | Hospitality | 2024 |
| Kprna House Ltd | Real estate | 2025 |
| Kprna Ltd | Real estate | 2024 |
| Kprna Rental LLP | | 2025 |
| Kprna Shop Ltd | Real estate | 2025 |
| KR & Daughters Properties Ltd | Real estate | 2024 |
| Kracho Limited | Wholesale & retail | 2025 |
| Krause Trans Ltd | Administrative & support | 2016 |
| Kraytum Ltd | Professional & scientific | 2025 |
| Kris LEE Accounting Ltd | Professional & scientific | 2015 |
| KRM03 Ltd | Information & communication | 2026 |
| Krystal Care and Support Services Ltd | Health & social care | 2025 |
| KS Contracting Ltd | Administrative & support | 2023 |
| KSB Prime Holdings Ltd | Real estate | 2025 |
| KSD Logistics Ltd | Administrative & support | 2017 |
| Ksenia Hygienist Ltd | Health & social care | 2026 |
| KSS Mini Store Limited | Wholesale & retail | 2023 |
| KTO Management Ltd | Administrative & support | 2022 |
| Kubad Property Ltd. | Real estate | 2025 |
| Kubas & Bear Property Holdings Ltd | Real estate | 2018 |
| Kubiesa Technology Ltd | Wholesale & retail | 2018 |