| Kalisi Homes Ltd | Real estate | 2026 |
| KAM G Transport Ltd | Transport & logistics | 2025 |
| Kamsham Limited | Hospitality | 2021 |
| Kancote Living Ltd | Hospitality | 2026 |
| Kang Construction Services Limited | Construction | 2020 |
| Kang Couriers UK Ltd | Transport & logistics | 2024 |
| Kankay Ltd | Information & communication | 2016 |
| Kanzen Global Limited | Wholesale & retail | 2016 |
| Kara Care Home Limited | Health & social care | 2014 |
| Kara Enterprise Limited | Hospitality | 2014 |
| Kara Properties Ltd | Construction | 2014 |
| Karemind Limited | Real estate | 2018 |
| Karen Myers Limited | Wholesale & retail | 2003 |
| Karnetic Limited | Wholesale & retail | 2014 |
| Kastaways Limited | Wholesale & retail | 2003 |
| KAT Financial Holdings Ltd | Real estate | 2025 |
| Kathayee Creations Ltd | Manufacturing | 2020 |
| Kattleya Limited | Wholesale & retail | 2021 |
| KAY CEE Holdings Limited | Real estate | 2015 |
| KAY Contractors Ltd | Manufacturing | 2023 |
| KAY100 Limited | Real estate | 2021 |
| Kayto Property Limited | Real estate | 2020 |
| Kbjk Bookkeeping Specialists Ltd | Professional & scientific | 2026 |
| Kcm-Logistics Ltd | Manufacturing | 2018 |
| KDI Brickwork Ltd | Construction | 2025 |
| KDK Discount Food & Wine Ltd | Wholesale & retail | 2013 |
| KDK Peri Peri Chicken Ltd | Hospitality | 2017 |
| KDP Construction Ltd | Construction | 2014 |
| Kebo Property Management Limited | Real estate | 2014 |
| Keep IT Warm Limited | Construction | 2020 |
| Keli Estates Ltd | Real estate | 2019 |
| Kelly Biggar Recruitment Ltd | Administrative & support | 2026 |
| Kelly's Cleaning and Maintenance Services Ltd | Administrative & support | 2023 |
| Keltel Security Limited | Wholesale & retail | 2016 |
| Kemwest Limited | Construction | 2010 |
| Kenburn Rentals Limited | Administrative & support | 1994 |
| Kenburn Waste Management Limited | Wholesale & retail | 1987 |
| Kensington Estate Holdings Limited | Financial services | 2021 |
| Kensworth (1996) Residents Company Limited | Administrative & support | 1996 |
| Kensworth Gate Management Limited | Administrative & support | 1989 |
| Kentruck Limited | Extraterritorial | 2003 |
| Kepada Services Ltd | Administrative & support | 2020 |
| Kepil Ltd | Hospitality | 2024 |
| Kerala Food Mart Limited | Hospitality | 2024 |
| Kerry Osborne Accountancy Services Limited | Professional & scientific | 2009 |
| Kerry Smith Plastering Limited | Construction | 2020 |
| Kettner Building Solutions Limited | Extraterritorial | 2007 |
| KEV Paving Ltd | Transport & logistics | 2024 |
| Kevchie Ltd | Wholesale & retail | 2022 |
| Kevghe Ltd | Administrative & support | 2025 |
| Kevin Bowkett Limited | Education | 2017 |
| Kevin LEA Management Ltd | Construction | 2023 |
| Kevin Thurston Transmission Services Limited | Wholesale & retail | 2015 |
| Key 2 Camden Limited | Real estate | 2026 |
| Key 2 Goldhurst Ltd | Real estate | 2020 |
| KEY2LONDON Ltd | Real estate | 2018 |
| Keyaan Accountancy Limited | Professional & scientific | 2015 |
| Keychainz Limited | Wholesale & retail | 2023 |
| Keyskips Limited | Administrative & support | 2016 |
| Keytoinvestments Ltd | Financial services | 2020 |
| KFH Property Ltd | Administrative & support | 1993 |
| Kfitzy Accountancy Ltd | Professional & scientific | 2015 |
| KG Restaurant Ltd | Hospitality | 2024 |
| Khalifa Automotive Solutions Ltd | Wholesale & retail | 2024 |
| Kham Ltd | Hospitality | 2018 |
| Khan & Co Restaurant Limited | Hospitality | 2019 |
| Khan & Daughters Ltd | Real estate | 2025 |
| KHG Property Solutions Limited | Professional & scientific | 2015 |
| Kidcation Events Ltd | Administrative & support | 2026 |
| Kiik Interiors Ltd | Construction | 2021 |
| Killer Prawns NW1 Limited | Hospitality | 2025 |
| KIM Ventures Limited | Wholesale & retail | 2005 |
| Kinesis Counselling and Development Ltd | Health & social care | 2016 |
| Kingdom Trading Ltd | Wholesale & retail | 2017 |
| Kingfisher Event Caterers Ltd | Administrative & support | 2010 |
| Kingoli Limited | Wholesale & retail | 2020 |
| Kings Flowers Ltd | Wholesale & retail | 2024 |
| Kingsbel Ltd | Wholesale & retail | 2020 |
| Kingsbury Property Maintenance Limited | Other services | 2021 |
| Kingsmen London Limited | Construction | 2016 |
| Kirby's & SON Limited | Real estate | 1986 |
| Kiri Trading Ltd | Health & social care | 2024 |
| Kirkstone Media Ltd | Information & communication | 2019 |
| Kitchen Fitter Ltd | Construction | 2025 |
| Kites Holdings Ltd | Real estate | 2024 |
| Kiwiors Trading Company Limited | Extraterritorial | 2013 |
| KJ Luxe Ltd | Administrative & support | 2024 |
| KJ Private Limited | Wholesale & retail | 2025 |
| KJD Plumbing & Heating Ltd | Construction | 2022 |
| Kjma Holdings Ltd | Real estate | 2026 |
| KK Car Wash Limited | Administrative & support | 2025 |
| Kkan Pharma Ltd | Wholesale & retail | 2019 |
| Kkan Trading Limited | Wholesale & retail | 2013 |
| KKB Property Developments Ltd | Construction | 2026 |
| KL Drinks Ltd | Wholesale & retail | 2025 |
| Kleanthous EA Ltd | Real estate | 2026 |
| KLM Natural Supplies Limited | Wholesale & retail | 2009 |
| Klpt Property Limited | Real estate | 2025 |
| Klyn AGL Limited | Financial services | 2024 |
| KM Orthopaedics Ltd | Health & social care | 2023 |