| Kelly's Construction (Luton) Ltd | Construction | 2008 |
| Kelmer Services and Trade Limited | Extraterritorial | 2022 |
| Kelsey Acoustics Limited | Manufacturing | 2014 |
| Kelvin MBA & Sons Ltd | Other services | 2018 |
| Kelyn Ltd | Construction | 2026 |
| Kemar's Property Services Ltd | Real estate | 2025 |
| Kemar’S Electrical Services Ltd | Manufacturing | 2021 |
| Kemsizzles UK Ltd | Hospitality | 2018 |
| KEN Logistics Ltd | Transport & logistics | 2024 |
| Ken-Ucheonye Healthcare Limited | Health & social care | 2013 |
| Kena Consultants Ltd. | Professional & scientific | 2011 |
| Kenefick Quantity Surveying Ltd | Professional & scientific | 2026 |
| Kenest Real Estate Limited | Real estate | 2023 |
| Kenex Logistics Ltd | Transport & logistics | 2021 |
| Kenexports Ltd | Administrative & support | 2013 |
| Kenfern Imports Ltd | Wholesale & retail | 2021 |
| Kenlaur Ltd | Health & social care | 2022 |
| Kenmore Property Investments Ltd | Real estate | 2024 |
| Kenna Electrical Ltd | Construction | 2008 |
| Keno Construction Limited | Construction | 2025 |
| Kenrow International Limited | Wholesale & retail | 2004 |
| Kensal Handling Systems Limited | Manufacturing | 2002 |
| Kensington Court Luton RTM Company Limited | Households | 2023 |
| Kensington Harrison Limited | Professional & scientific | 2012 |
| Kensington Traders Limited | Manufacturing | 1985 |
| Kensingtons (London) Limited | Real estate | 2020 |
| Kensworth Supermarket Limited | Wholesale & retail | 2012 |
| Kent and Essex Builders Limited | Construction | 2024 |
| Kent Leisure Parks Limited | Administrative & support | 2005 |
| Kentcase Limited | Hospitality | 2024 |
| Kentish Fast Food Holdings Ltd | Financial services | 2025 |
| Kenton One Ltd | Wholesale & retail | 2025 |
| Kenz Digital Limited | Wholesale & retail | 2025 |
| Kerala Express Ltd | Hospitality | 2024 |
| Kershaw Rail Limited | Transport & logistics | 2014 |
| Kescar International Ltd | Wholesale & retail | 2024 |
| Kesja's Health Care Services Ltd | Public administration | 2019 |
| Kestral Ventures Limited | Construction | 2003 |
| Kestrel Corporation Ltd | Financial services | 2022 |
| Kestrello Ltd | Wholesale & retail | 2026 |
| KETO4LESSKILOS Ltd | Wholesale & retail | 2020 |
| KEV Home Improvements Ltd | Construction | 2023 |
| Kevden Ltd | Manufacturing | 2023 |
| Kewi Corp Ltd | Wholesale & retail | 2024 |
| Key Accountancy and Tax Ltd | Professional & scientific | 2017 |
| Key Emporio Limited | Health & social care | 2023 |
| Key Security Centre Ltd | Administrative & support | 2017 |
| Key Sterling Limited | Other services | 2014 |
| Keygate Properties Ltd | Real estate | 2025 |
| Keymaths Limited | Hospitality | 2017 |
| Keynest Rentals Ltd | Real estate | 2024 |
| Keys 4 Cannes Ltd | Real estate | 2018 |
| Keystage C.I.C. | Real estate | 2011 |
| Keystage Housing C.I.C. | Hospitality | 2018 |
| Keystone Luton Estate Agents Limited | Real estate | 2017 |
| Keystone Security Services Limited | Administrative & support | 2020 |
| Kezo Investment Holding Limited | Real estate | 2026 |
| Kfmh Investments Ltd | Administrative & support | 2019 |
| Kfmh Properties Ltd | Real estate | 2021 |
| KFR-K9 Ltd | Administrative & support | 2024 |
| KG Auto Ltd | Wholesale & retail | 2018 |
| KG Automotive Consultancy Limited | Wholesale & retail | 2024 |
| KG Mortgage Solutions Ltd | Financial services | 2025 |
| KG Wears Ltd | Wholesale & retail | 2025 |
| KGA Property Ltd | Real estate | 2023 |
| KGK Healthcare Limited | Health & social care | 2016 |
| KH Capital Holdings Limited | Financial services | 2025 |
| KH Taxi Ltd | Transport & logistics | 2020 |
| KH11ZER Limited | Professional & scientific | 2023 |
| KH2 Services Limited | Real estate | 2023 |
| Khaani Limited | Hospitality | 2019 |
| Khaanj Ltd | Wholesale & retail | 2019 |
| Khadija & Fathima Limited | Transport & logistics | 2018 |
| Khadija Naeem Limited | Financial services | 2016 |
| Khadija&Co Ltd | Wholesale & retail | 2024 |
| Khadijah Investments Luton Limited | Real estate | 2026 |
| Khadijah Islamic Store Ltd | Wholesale & retail | 2017 |
| Khadijaz Ltd | Wholesale & retail | 2022 |
| Khaffou Import & Export Ltd | Wholesale & retail | 2024 |
| Khal's Driving School Limited | Education | 2023 |
| Khamisani Ventures Ltd | Wholesale & retail | 2025 |
| Khan & Co Goldsmiths Ltd | Wholesale & retail | 2025 |
| Khan Automotive Ltd | Wholesale & retail | 2019 |
| Khan Builder Hub Limited | Construction | 2021 |
| Khan Cars Rental Ltd | Wholesale & retail | 2016 |
| Khan Darbar Ltd | Hospitality | 2025 |
| Khan Gadgets Ltd | Wholesale & retail | 2025 |
| Khan Meat House Limited | Wholesale & retail | 2026 |
| Khan Medical Limited | Health & social care | 2019 |
| Khan Restaurant Ltd | Hospitality | 2025 |
| Khan Tutoring Ltd | Education | 2025 |
| Khan TV and Film Limited | Professional & scientific | 2022 |
| Khan UK Estates Ltd | Real estate | 2022 |
| Khan's Chicken & Rice Ltd | Hospitality | 2024 |
| Khan's Supermarket Ltd | Wholesale & retail | 2022 |
| Khan's Superstore Ltd | Wholesale & retail | 2024 |
| Khangura Construction Limited | Construction | 2016 |
| Khanom Ltd | Health & social care | 2022 |
| Khansultant Ltd | Professional & scientific | 2013 |
| Khanta Build Ltd | Construction | 2025 |