| K & K Consultancy and Training Limited | Professional & scientific | 2018 |
| K & M Hulme (Properties) Limited | Real estate | 1991 |
| K & M Locums Limited | Health & social care | 2018 |
| K & M Property Developers Ltd | Real estate | 2026 |
| K B Atherton Limited | Professional & scientific | 2024 |
| K H Plant Services Ltd | Manufacturing | 2011 |
| K J C Watch Services Limited | Other services | 2010 |
| K Jones Interiors Limited | Professional & scientific | 2020 |
| K M Huntbach Ltd | Health & social care | 2021 |
| K Rothery & SON Limited | Construction | 2007 |
| K&K Hospitality Ltd | Hospitality | 2021 |
| K&P Surveyors Ltd | Professional & scientific | 2015 |
| K.P.C. Book Protection Limited | Manufacturing | 1999 |
| K3 Creative Ltd | Wholesale & retail | 2020 |
| K4MMY Ltd | Transport & logistics | 2026 |
| K9 Patrol Delta Security Ltd | Administrative & support | 2025 |
| KA and MS Properties Ltd | Real estate | 2024 |
| KA Dentalcare Ltd | Health & social care | 2023 |
| KA IT Development Limited | Administrative & support | 2012 |
| KA Realty Ltd | Real estate | 2023 |
| Kabechi Ltd | Wholesale & retail | 2021 |
| Kaboodell Limited | Professional & scientific | 2018 |
| Kact Life Ltd | Health & social care | 2025 |
| Kahuka Limited | Financial services | 2018 |
| KAI Ziya Properties Limited | Real estate | 2025 |
| Kaiiyra Events Ltd | Other services | 2025 |
| Kaisrs Ltd | Transport & logistics | 2026 |
| Kaka Limited | Administrative & support | 2015 |
| Kalam Spice TA Cardamon Restaurant Ltd | Hospitality | 2025 |
| Kall Kwik Machinery Limited | Professional & scientific | 2018 |
| Kamatcho Geni Ltd | Wholesale & retail | 2024 |
| Kamran Balti House Ltd | Hospitality | 2023 |
| Kamran Consultancy Ltd | Administrative & support | 2017 |
| Kanika Limited | Administrative & support | 2005 |
| Kanraz Limited | Information & communication | 2017 |
| Kapt Limited | Real estate | 2024 |
| Karbon B1 Ltd | Wholesale & retail | 2019 |
| Karen LY Property Management Ltd | Real estate | 2014 |
| Karian Parks Ltd | Wholesale & retail | 2024 |
| Karls KIT Bags (Embroidery Services) Limited | Other services | 2015 |
| Karrt Business Limited | Households | 2024 |
| Karwan-Al-Madinah Tour Operators Limited | Administrative & support | 2004 |
| KAS Trade Ltd | Wholesale & retail | 2023 |
| Kash Afro Caribbean Food Ltd | Wholesale & retail | 2023 |
| Kashmir HX Hot & Spicy Ltd | Hospitality | 2026 |
| Kashmir Travel Ltd | Transport & logistics | 2024 |
| Kaspian Investments Limited | Real estate | 2014 |
| Kate Lycett Limited | Arts & recreation | 2017 |
| Kate's Cottage Skye Ltd | Hospitality | 2025 |
| Kathken Ltd | Financial services | 2026 |
| Kathryn Hurl Counselling & Therapies Ltd | Health & social care | 2025 |
| Katie Gledhill Ltd | Other services | 2019 |
| Kaya Grill 1 Ltd | Hospitality | 2024 |
| Kaya's Grill Ltd | Hospitality | 2023 |
| Kayan Property Investments Ltd | Real estate | 2023 |
| Kaye & Co. (Huddersfield) Limited | Professional & scientific | 1922 |
| Kaysaan & Co Ltd | Wholesale & retail | 2024 |
| Kayu Food & Wine Limited | Wholesale & retail | 2024 |
| Kazimiya Group Ltd | Real estate | 2025 |
| KB & DB Ltd | Construction | 2019 |
| KB Risk Consulting Limited | Professional & scientific | 2007 |
| KBR Adviser Services Limited | Financial services | 2013 |
| KBT Cleaning Ltd | Administrative & support | 2026 |
| Kcdent Ltd | Health & social care | 2024 |
| Kcollins Limited | Transport & logistics | 2025 |
| KDE Catering Equipment Limited | Administrative & support | 2023 |
| KDH Energy Limited | Professional & scientific | 2012 |
| KDN Engineering Limited | Manufacturing | 2004 |
| KDT Accountancy & Taxation Services Ltd | Professional & scientific | 2011 |
| Kedel Limited | Manufacturing | 2010 |
| Keegan Ford Sponsorship Limited | Other services | 2002 |
| Keenan Reeves Ltd | Wholesale & retail | 2025 |
| Keep in Mind Limited | Health & social care | 2021 |
| Keep Safe Self Storage Limited | Administrative & support | 1996 |
| Keep Safe Storage Limited | Administrative & support | 2009 |
| Keeping Others Safe Ltd | Extraterritorial | 2024 |
| Keighley Building Plastics & Drainage Centre Limited | Wholesale & retail | 2021 |
| Keighley Road Surgery Ltd | Health & social care | 2024 |
| Keighley Stairtreads Limited | Wholesale & retail | 1978 |
| Keith's Couriers Ltd | Transport & logistics | 2025 |
| Kellett Engineering Company Limited | Manufacturing | 1946 |
| Kellett Property Holdings Limited | Real estate | 2025 |
| Kelly Devlin Ltd | Professional & scientific | 2022 |
| KEM11 Holdings Limited | Real estate | 2015 |
| Kemp Waste Management Limited | Water & waste | 2007 |
| Kenefick Optical Limited | Professional & scientific | 2018 |
| Kenith Limited | Real estate | 2009 |
| Kennedy Plumbing and Heating Ltd | Construction | 2017 |
| Kenneth Todd & SON Limited | Wholesale & retail | 2018 |
| Kenworthy’S Development Ltd | Construction | 2025 |
| Kerr Services Ltd | Construction | 2019 |
| Kerry Family Investments Limited | Financial services | 2024 |
| Kesi Property Ltd | Real estate | 2017 |
| Kevco Limited | | 1988 |
| Kevin P Ltd | Wholesale & retail | 2022 |
| Kevin Page Electrical Limited | Construction | 2014 |
| Kevin Redfern Onsite Services Limited | Professional & scientific | 2019 |
| Kevin Redfern Valve Services Ltd | Professional & scientific | 2026 |
| Key Choice Insurance Marketing Limited | Financial services | 2002 |
| Key Land Properties Ltd | Real estate | 2023 |