| Kainos Ventures Limited | Real estate | 2025 |
| Kairo Growth Ltd | Information & communication | 2025 |
| Kaiza Travel Services Limited | Transport & logistics | 2016 |
| Kaizemi Ltd | Transport & logistics | 2026 |
| Kaizen Media Ltd | Information & communication | 2025 |
| Kaizen Pro Ltd | Professional & scientific | 2021 |
| Kaizen Psychology Ltd | Health & social care | 2021 |
| Kaizen Summit Ltd | Professional & scientific | 2024 |
| Kaizen Supply Co. Ltd | Manufacturing | 2025 |
| Kaizenpm Ltd | Real estate | 2024 |
| Kaizer Productions (UK) Limited | Information & communication | 2024 |
| Kaizoruu Nexus Ltd | Information & communication | 2026 |
| Kakacards Ltd | Wholesale & retail | 2025 |
| Kakama Ltd | Wholesale & retail | 2025 |
| KAL Properties Limited | Real estate | 2013 |
| Kalarjian Delta Ltd | Transport & logistics | 2025 |
| Kalathil Medics Limited | Real estate | 2021 |
| Kaleidoscope Creations Ltd | Wholesale & retail | 2025 |
| Kaleidoscope. Advertising. Design. Marketing Ltd. | Information & communication | 1987 |
| Kaleto Digital Ltd | Professional & scientific | 2025 |
| Kalimera Ltd | Hospitality | 2025 |
| Kallico Property Group Ltd | Real estate | 2026 |
| Kallys Properties LLP | | 2006 |
| Kalmon Ltd | Transport & logistics | 2021 |
| Kaloco CIC | Education | 2026 |
| Kalra Medical Services Ltd | Health & social care | 2021 |
| KAM FAY VON Ltd | Hospitality | 2020 |
| KAM Property Group Ltd | Real estate | 2020 |
| KAM the Assessor Ltd | Extraterritorial | 2024 |
| Kamal Properties Limited | Real estate | 2002 |
| Kamil Hreniak Trans Ltd | Transport & logistics | 2019 |
| Kamil Kobrzak Transport Ltd. | Transport & logistics | 2013 |
| Kamishi Limited | Administrative & support | 2024 |
| Kammodity Shop Ltd | Wholesale & retail | 2026 |
| Kamran Rasul Limited | Health & social care | 2019 |
| Kanaval Consultancy Limited | Professional & scientific | 2020 |
| Kandy Express Ltd | Wholesale & retail | 2026 |
| Kane Flooring Limited | Construction | 2018 |
| Kane Hodges LP | | 2011 |
| Kanee RR Ltd | Wholesale & retail | 2023 |
| Kang Designs Ltd | Wholesale & retail | 2025 |
| Kangfoodz Ltd | Hospitality | 2025 |
| Kanmalai Properties Ltd | Real estate | 2025 |
| Kanmalaitech UK Limited | Information & communication | 2024 |
| Kano's Trapkitchen Ltd | Hospitality | 2024 |
| Kanpeki Development Consultants Ltd | Real estate | 2022 |
| Kanpeki Property Solutions Limited | Real estate | 2020 |
| Kanpeki Surface Solutions Ltd | Construction | 2025 |
| Kanteh & Enterprise Ltd | Wholesale & retail | 2024 |
| Kantel-Johnson Enterprise Ltd | Wholesale & retail | 2025 |
| Kanz Ltd | Wholesale & retail | 2025 |
| Kanzul Emaan Ltd | Education | 2026 |
| Kaondeka Community Services CIC | Administrative & support | 2021 |
| Kaondeka Global Solutions Ltd | Professional & scientific | 2026 |
| Kaos Creative Arts and Wellbeing CIC | Education | 2026 |
| KAP Developments (NW) Limited | Construction | 2024 |
| Kapa Catering Ltd | Hospitality | 2024 |
| Kapan Holding Limited | Hospitality | 2023 |
| Kapo (NW) Ltd | Wholesale & retail | 2021 |
| Kappa Packaging UK Pension Schemes Limited | Administrative & support | 1951 |
| Kaps Contracts Ltd | Administrative & support | 2025 |
| Kapso Ltd | Wholesale & retail | 2026 |
| Kapucia Ltd | Other services | 2015 |
| KAR Coaching Ltd | Professional & scientific | 2015 |
| KAR Consultants Limited | Professional & scientific | 2008 |
| KAR Systems Ltd | Construction | 2021 |
| KAR Transport & Deliveries Ltd | Manufacturing | 2020 |
| Karak Chaiwala Limited | Hospitality | 2025 |
| Karar Limited | Real estate | 2019 |
| Karawool Ltd | Other services | 2026 |
| Kareegar Limited | Wholesale & retail | 2026 |
| Kareem Formby Ltd | Hospitality | 2024 |
| Karen Hogan Ltd | Health & social care | 2025 |
| Karen Moss Limited | Professional & scientific | 2024 |
| Karen Parks Estate Agents Limited | Real estate | 2025 |
| Karen Parks Sales and Lettings Limited | Real estate | 2009 |
| Karen Size Therapy and Consultancy Ltd | Health & social care | 2022 |
| Karena Artisan Florist Ltd | Wholesale & retail | 2019 |
| Karim Liverpool Limited | Manufacturing | 2024 |
| Karimi 135 Ltd | Real estate | 2019 |
| Karko Ltd | Transport & logistics | 2015 |
| Karl Fischer Garden Grounds & Tree Maintenance Limited | Administrative & support | 2020 |
| Karl Skeggs T/A Upper Cutz Ltd | Other services | 2013 |
| Karla Ambrose Aesthetics Clinic Ltd | Other services | 2025 |
| Karlix Ltd | Wholesale & retail | 2025 |
| Karls Cars North West Ltd | Wholesale & retail | 2026 |
| Karlsson Installations Ltd | Construction | 2021 |
| Karm Research Group Limited | Professional & scientific | 2011 |
| Karman Services Ltd | Administrative & support | 2025 |
| Karmellhi Group Limited | Professional & scientific | 2025 |
| Karnak Publishing Ltd | Wholesale & retail | 2022 |
| Karneem Limited | Administrative & support | 2020 |
| Karo Shawarma Ltd | Hospitality | 2025 |
| Karo's Burgers Ltd | Hospitality | 2019 |
| Karolina Tax Ltd | Professional & scientific | 2022 |
| Kartar Sahota & Sons Limited | Hospitality | 2007 |
| Karuna Wellbeing Ltd | Health & social care | 2019 |
| Karvan Canal Trading Limited | Wholesale & retail | 2025 |
| Karvan Limited | Health & social care | 2014 |
| Karwan Logistic Ltd | Transport & logistics | 2025 |