| Kingsdale Court Newport RTM Company Limited | Households | 2020 |
| Kingsdown Enterprises Cumbria Limited | Real estate | 2012 |
| Kingsguards Ltd | Financial services | 2020 |
| Kingshield Contractors (Cambs) Ltd | Construction | 2019 |
| Kingsman Biotech Ltd | Professional & scientific | 2017 |
| Kingsman Capital Co. Ltd. | Professional & scientific | 2015 |
| Kingsman Management Co. Ltd. | Professional & scientific | 2015 |
| Kingsmead Assets Limited | Financial services | 2013 |
| Kingston City Properties Limited | Real estate | 2007 |
| Kingston Medical Equipment and Garments Ltd | Manufacturing | 2021 |
| Kingston Travel Limited | Administrative & support | 2019 |
| Kingstone Estates Limited | Real estate | 2018 |
| Kingstone Ventures Ltd | Wholesale & retail | 2024 |
| Kingswood Capital Partners Ltd | Real estate | 2017 |
| Kingswood Mortgage Solutions Ltd | Financial services | 2021 |
| Kingswood Property Trading Limited | Financial services | 2013 |
| Kington Dental Practice Ltd | Health & social care | 2023 |
| Kinlee Holdings Limited | Financial services | 2020 |
| Kinlee Investments Limited | Arts & recreation | 2020 |
| Kinoyee Group Limited | Financial services | 2025 |
| Kinranstar Co., Ltd | Wholesale & retail | 2025 |
| Kinsei Strategies Ltd | Information & communication | 2026 |
| Kinsera Holdings Ltd | Financial services | 2026 |
| Kinshomas Limited | Wholesale & retail | 2025 |
| Kinsung Import and Export Co., Ltd | Professional & scientific | 2013 |
| Kinswell Property Management Ltd | Households | 2018 |
| Kintaro Limited | Hospitality | 2024 |
| Kinvarra Ltd | Health & social care | 2024 |
| Kinway (UK) International Limited | Professional & scientific | 2007 |
| KIO NIM Ltd | Wholesale & retail | 2025 |
| Kione Ventures Limited | Wholesale & retail | 2015 |
| KIP Mcgrath Education Centre Bridgend Limited | Education | 2020 |
| KIP Mcgrath Education Centre Cardiff West Limited | Education | 2014 |
| Kira Fire & Security Systems Limited | Administrative & support | 2013 |
| Kira Footcare Limited | Health & social care | 2021 |
| Kirakgate Shop Limited | Agriculture & fishing | 2025 |
| Kiralid Ltd | Wholesale & retail | 2022 |
| Kiran Gill Ltd | Financial services | 2019 |
| Kirby Electrical Contractors Limited | Construction | 2008 |
| Kire Group Ltd | Financial services | 2025 |
| Kiri Event Management Limited | Wholesale & retail | 2022 |
| Kirk Boyd Productions Ltd. | Administrative & support | 2025 |
| Kirk's Garage (Wolverhampton) Limited | Wholesale & retail | 2018 |
| Kirkaig Foods Ltd | Hospitality | 2013 |
| Kirke Creative Ltd | Wholesale & retail | 2026 |
| Kirkhill Group (Cardiff) Ltd | Wholesale & retail | 2025 |
| Kirkhill Group Ltd | Wholesale & retail | 2024 |
| Kirkhollow Ltd | Extraterritorial | 2008 |
| Kirmit Productions Ltd | Arts & recreation | 2020 |
| Kirol Lettings Ltd | Real estate | 2019 |
| Kirollos Ltd | Wholesale & retail | 2025 |
| Kirov Services Ltd | Construction | 2019 |
| Kirsten Wilson Consulting Ltd | Information & communication | 2025 |
| Kish Delight Ltd | Hospitality | 2017 |
| Kislali Ltd | Wholesale & retail | 2025 |
| Kiss Graphics Leeds Ltd | Manufacturing | 2018 |
| Kisseh Ltd | Manufacturing | 2024 |
| KIT Parkington Kitchens Limited | Construction | 2018 |
| KIT Price Ltd | Professional & scientific | 2023 |
| Kitch Belfast Ltd | Hospitality | 2019 |
| Kitchen Economy Holdings Limited | Financial services | 2022 |
| Kitchen Economy Limited | Wholesale & retail | 2015 |
| Kitchen Karaoke Superstars Ltd | Manufacturing | 2025 |
| Kitchen Karma Ltd | Hospitality | 2019 |
| Kitchen Repair Services Limited | Manufacturing | 2012 |
| Kitchen Wizard Limited | Manufacturing | 2016 |
| Kitchen Worktop Company Limited | Construction | 2016 |
| Kitchenware Distributions Ltd | Wholesale & retail | 2019 |
| Kitchoryn Ltd | Professional & scientific | 2025 |
| Kitchsculpt Ltd | Professional & scientific | 2025 |
| Kitcihin Art Ltd | Wholesale & retail | 2025 |
| Kite for Events Ltd | Information & communication | 2023 |
| Kite Recruitment Ltd | Professional & scientific | 2025 |
| Kith & KIN Studio Ltd | Professional & scientific | 2026 |
| Kiti CYF | Wholesale & retail | 2012 |
| Kitos Limited | Wholesale & retail | 2025 |
| Kitsl Mart Ltd | Wholesale & retail | 2025 |
| Kitson's Environmental Services Limited | Wholesale & retail | 1974 |
| Kittie Productions Limited | Information & communication | 2021 |
| Kitty LEE Limited | Extraterritorial | 2021 |
| Kittycatcorp Limited | Transport & logistics | 2026 |
| Kittypot Ltd | Information & communication | 2021 |
| Kiwf Holdings Ltd | Real estate | 2019 |
| Kiwi AI Limited | Information & communication | 2023 |
| Kiwi Film House Ltd | Information & communication | 2017 |
| Kiwi Financial Group Ltd. | Other services | 2017 |
| Kiwis Bowls Ltd | Wholesale & retail | 2024 |
| Kizeron Limited | Information & communication | 2018 |
| KJ Drains Ltd | Water & waste | 2019 |
| KJ Regan & Associates Limited | Professional & scientific | 2013 |
| Kjag Acquisitions Ltd | Administrative & support | 2025 |
| Kjanos Haulage Limited | Transport & logistics | 2019 |
| KJB Comms Limited | Information & communication | 2016 |
| Kjbn Holdings Ltd | Financial services | 2024 |
| KJG Real Estate Ltd | Real estate | 2026 |
| KJH Corporation Limited | Information & communication | 2013 |
| Kjjj Ltd | Wholesale & retail | 2025 |
| KJM Consultancy Services Ltd | Professional & scientific | 2021 |
| KJM Homes Ltd | Real estate | 2020 |
| KJM Mortgage & Protection Services Limited | Financial services | 2018 |