| K9 Outpaws Ltd | Other services | 2024 |
| Kaeleron Ltd | Information & communication | 2026 |
| Kaes Consulting Ltd | Professional & scientific | 2025 |
| Kaes Rehab Ltd | Health & social care | 2025 |
| KAI Keogh Design & Development Ltd | Construction | 2023 |
| Kaia Sustainability Consulting Ltd | Professional & scientific | 2024 |
| Kalamazoo Dermatology Ltd | Health & social care | 2024 |
| Kaloudis Limited | Health & social care | 2025 |
| Kamani Groups GB Ltd | Professional & scientific | 2019 |
| Kamino Technology Group Ltd | Information & communication | 2025 |
| Kamnar Investments Ltd | Financial services | 2015 |
| Kanagala Cardiology Limited | Health & social care | 2022 |
| Kangablu Ltd | Health & social care | 2012 |
| KAO Holdings Limited | Financial services | 2018 |
| Kapam Limited | Real estate | 2017 |
| Kapoor Medicolegal Reports Limited | Health & social care | 2024 |
| Karman Digital Limited | Information & communication | 2020 |
| Karski Orthopaedics Limited | Health & social care | 2013 |
| Kate Park Events Limited | Arts & recreation | 2014 |
| Kathryn Hudson Consulting Limited | Professional & scientific | 2025 |
| Katie Laura Limited | Other services | 2024 |
| Kato Limited | Information & communication | 2016 |
| Katy Leeson Limited | Professional & scientific | 2024 |
| Kaye Belmonte Ltd | Professional & scientific | 2026 |
| Kazar PL Limited | Health & social care | 2022 |
| KB Medical Group Ltd | Health & social care | 2026 |
| Kb&C Limited | Construction | 2025 |
| KB10 Enterprises Ltd | Real estate | 2024 |
| KBF Psychotherapy & Life Transformation Ltd | Health & social care | 2022 |
| KBK Meal Prep Limited | Hospitality | 2019 |
| Kbusm Limited | Arts & recreation | 2024 |
| KC Golf Ltd | Professional & scientific | 2026 |
| KC Logistics (UK) Limited | Transport & logistics | 2013 |
| Kcbm Limited | Health & social care | 2026 |
| KD Kitchen Design Services Ltd | Professional & scientific | 2018 |
| Kdatc Limited | Professional & scientific | 2012 |
| Keisuke UK Ltd | Wholesale & retail | 2005 |
| Kelf Commercial Holdings Ltd | Real estate | 2022 |
| Kelf Holdings Ltd | Real estate | 2022 |
| Kelros Limited | Other services | 1996 |
| Kelvingrove Scott Solutions Ltd | Information & communication | 2025 |
| KEN Bishop Consulting Limited | Professional & scientific | 2018 |
| Kendall Medical Ltd | Health & social care | 2017 |
| Kenhale Ltd | Real estate | 2009 |
| Kenner AV Solutions Limited | Wholesale & retail | 2009 |
| Kennerley Court (Wilmslow) Maintenance Company Limited | Households | 1986 |
| Kenny Orthopaedics Limited | Health & social care | 2010 |
| Kent & Medway Healthcare Solutions LLP | | 2024 |
| Kent and London Cardiology Limited | Health & social care | 2022 |
| Kent Breast and Plastic Surgery Limited | Health & social care | 2022 |
| Kepczyk Sanderson + Associates Limited | Professional & scientific | 2018 |
| Keran Williams Consulting Ltd | Professional & scientific | 2024 |
| Kerellos Shoukier Limited | Health & social care | 2023 |
| Kerriline Developments Ltd | Real estate | 2009 |
| Kersal Road Limited | Real estate | 2023 |
| Kershaw Estates Ltd | Real estate | 2012 |
| Kerslake Healthcare Limited | Health & social care | 2018 |
| Kevo Group Ltd | Construction | 2021 |
| Kevo Holdings Ltd | Financial services | 2022 |
| Kevo Investments Ltd | Construction | 2021 |
| Key and Eagle Digital Media Ltd | Information & communication | 2020 |
| Key Management Support Limited | Professional & scientific | 2010 |
| Key Prep Civils Limited | Construction | 2026 |
| Keybored Ltd | Information & communication | 2023 |
| Keynote Educational Limited | Education | 2011 |
| Keynote Training Limited | Administrative & support | 2008 |
| KGA Capital Limited | Professional & scientific | 2018 |
| Khan Mulla Limited | Health & social care | 2023 |
| Khan Surgical Services Ltd | Health & social care | 2013 |
| Khani Consulting Ltd | Health & social care | 2026 |
| Khayam Sheikh Ltd | Health & social care | 2017 |
| Kieran Power Plastic Surgery Limited | Health & social care | 2019 |
| Kilcommons Investments Ltd | Real estate | 2026 |
| Kilcommons Maloney Limited | Construction | 2017 |
| Kilmal Property Ltd | Real estate | 2018 |
| Kiln Croft Lane Retail Park HCW Ltd | Other services | 2019 |
| KIM Rajappan Limited | Health & social care | 2012 |
| Kinder View Close Management Limited | Households | 2019 |
| Kinetic + Ltd | Information & communication | 2013 |
| Kinetic Plus Group Limited | Financial services | 2026 |
| Kings Tree Innovations Limited | Health & social care | 2016 |
| Kingsford Wealth Management Ltd | Financial services | 2021 |
| Kingsway Asset Finance Ltd | Financial services | 1995 |
| Kingsway Finance and Leasing Limited | Financial services | 1995 |
| Kingsway Finance Limited | Financial services | 2008 |
| Kingsway Financial Group Holdings Limited | Financial services | 1997 |
| Kingsway Leasing Limited | Financial services | 1997 |
| Kinkladze Ltd | Professional & scientific | 2024 |
| Kirk Investment Holdings Ltd | Real estate | 2021 |
| Kirton Safety (Health and Safety Consultancy) Ltd | Professional & scientific | 2025 |
| Kitecreative Ltd | Manufacturing | 2014 |
| Kiwi Commerce Ltd | Information & communication | 2018 |
| KJB Holdings (Cheshire) Limited | Financial services | 2024 |
| KJB Properties (Cheshire) Ltd | Real estate | 2024 |
| Kleaning Services Ltd | Administrative & support | 2026 |
| KM Ventures 3 Limited | Hospitality | 2023 |
| KM Ventures 5 Limited | Hospitality | 2023 |
| KMB Medical Limited | Health & social care | 2023 |
| KMS Diagnostics Limited | Health & social care | 2023 |
| Knect Clothing Ltd | Wholesale & retail | 2025 |