| K&V Aluminium SYS Ltd | Manufacturing | 2019 |
| K-Car Autos Ltd | Wholesale & retail | 2025 |
| K-Mor Construction Ltd | Construction | 2021 |
| K-Mor Contracts Limited | Construction | 2002 |
| K-Mor Installations Limited | Construction | 2016 |
| K-Rail-Tech Ltd | Professional & scientific | 2016 |
| K.A.V. Services Ltd | Professional & scientific | 2019 |
| K.L.S Commercial Property Ltd | Real estate | 2023 |
| K.W.C. (Chichester) Limited | Households | 2016 |
| K2 Garage Services Ltd | Wholesale & retail | 2018 |
| K2B Mototek Ltd | Wholesale & retail | 2025 |
| K3 Accountants Limited | Professional & scientific | 2017 |
| K9 Wellbeing Support Ltd | Professional & scientific | 2023 |
| K9KLEIN Ltd | Wholesale & retail | 2023 |
| KAG Property Developments Ltd | Agriculture & fishing | 2020 |
| Kaikoura Building and Carpentry Limited | Construction | 2026 |
| Kaikoura Limited | Professional & scientific | 2021 |
| Kaleidoscope Music Limited | Information & communication | 2010 |
| Kanga Productions Ltd | Transport & logistics | 2026 |
| Kanyuchi Limited | Health & social care | 2013 |
| Karandikar Dental Limited | Health & social care | 2025 |
| Karate to Inspire Limited | Education | 2022 |
| Karen Kirkpatrick Ltd | Health & social care | 2025 |
| Karma Play Limited | Information & communication | 2017 |
| Kase Properties Ltd | Real estate | 2019 |
| Kate E JAY Health Ltd | Health & social care | 2023 |
| Kate Grosvenor Corporate Wellness Ltd | Professional & scientific | 2024 |
| Kate Preston Salons Limited | Other services | 2014 |
| Kathryn Andrews Books Limited | Information & communication | 2020 |
| Katnic Services Limited | Other services | 2016 |
| Katong Property Investment Ltd | Real estate | 2017 |
| Kaves Automotive Ltd | Wholesale & retail | 2024 |
| Kaves Investments Ltd | Households | 2024 |
| KAY Mechanical Limited | Construction | 2016 |
| Kayospruce Holdings Limited | Wholesale & retail | 2022 |
| Kayospruce Limited | Wholesale & retail | 1983 |
| Kayte Ellis Agency Ltd | Professional & scientific | 2012 |
| Kayte Ellis Limited | Professional & scientific | 2022 |
| KB Accountants Limited | Professional & scientific | 2016 |
| Kbbra Limited | Wholesale & retail | 2022 |
| KC Services (South East) Limited | Wholesale & retail | 2025 |
| KCC Limited | Manufacturing | 1997 |
| Kcduk Limited | Wholesale & retail | 2024 |
| KD Enterprises Ltd | Hospitality | 2023 |
| KD Fire and Security Ltd | Public administration | 2024 |
| KD Quality Management Services Ltd | Professional & scientific | 2025 |
| Kdska Ajkal Limited | Wholesale & retail | 2025 |
| Keats Consulting Ltd | Real estate | 2014 |
| Keats Property Management Ltd | Real estate | 2024 |
| Kedoad Ltd | Professional & scientific | 2025 |
| Keeping IT Clean Ltd | Administrative & support | 2024 |
| Keflon Limited | Manufacturing | 1983 |
| Keighley Specsavers Hearcare Limited | Wholesale & retail | 2017 |
| Keighley Specsavers Limited | Wholesale & retail | 1992 |
| Keighley Visionplus Limited | Wholesale & retail | 1992 |
| Keiky Limited | Professional & scientific | 2012 |
| Keith Bradley Engineering Co. Limited | Manufacturing | 1976 |
| Kellow Marine Ltd | Manufacturing | 2025 |
| Kellys Tradings Ltd | Wholesale & retail | 2013 |
| Kelvin Inspires Ltd | Professional & scientific | 2020 |
| Kelvion Limited | Manufacturing | 2000 |
| Kelvora Ltd | Professional & scientific | 2024 |
| Kenbrook Limited | Construction | 2019 |
| Kendal Mint Bridge Specsavers Limited | Wholesale & retail | 2018 |
| Kendal Plumbing and Heating Ltd | Manufacturing | 2003 |
| Kendrick Wolff Ltd | Professional & scientific | 2020 |
| Kenice International Ltd | Professional & scientific | 2017 |
| Kenilworth Specsavers Hearcare Limited | Wholesale & retail | 2024 |
| Kenilworth Specsavers Limited | Wholesale & retail | 2008 |
| Kenilworth Visionplus Limited | Wholesale & retail | 2008 |
| Kenny Cultural Development Co., Ltd. | Wholesale & retail | 2022 |
| Kennys IT & Computer Solutions Ltd | Information & communication | 2018 |
| Kens Peri Peri Fareham Ltd | Hospitality | 2017 |
| Kensington Cromwell Road Specsavers Limited | Wholesale & retail | 2018 |
| Kensington Homes (IOW) Limited | Construction | 2003 |
| Kensington Homes Limited | Construction | 2001 |
| Kensington Manor Farm Ltd | Real estate | 2011 |
| Kensley Global Limited | Wholesale & retail | 2024 |
| Kent Cctv and Data Limited | Information & communication | 2018 |
| Kent Engineers Ltd | Construction | 2015 |
| Kent Fencing and Landscaping Ltd | Construction | 2021 |
| Kent Joinery Limited | Manufacturing | 2021 |
| Kermore Limited | Real estate | 2000 |
| Kerricor UK Limited | Information & communication | 2018 |
| Kerry Marine Engineering Ltd | Manufacturing | 2020 |
| Keston Capital Limited | Real estate | 2021 |
| Kestrel House School Limited | Professional & scientific | 2010 |
| Kestrel Property Developments Ltd | Construction | 2025 |
| Kettering Specsavers Hearcare Limited | Wholesale & retail | 2006 |
| Kettering Specsavers Limited | Wholesale & retail | 1989 |
| Kettering Visionplus Limited | Wholesale & retail | 2000 |
| Kevin Cawley Limited | Wholesale & retail | 2026 |
| Kevin March Financial Consultancy Limited | Other services | 2010 |
| Kevin Woods Equity Release Specialist Limited | Financial services | 2013 |
| Kevinoz Decals Ltd | Wholesale & retail | 2024 |
| Key Diamond Properties Ltd | Real estate | 2024 |
| Key Health Partnership Ltd | Financial services | 2009 |
| Key Personnel Management Limited | Administrative & support | 2004 |
| Keynor Electrical Ltd | Professional & scientific | 2023 |
| Keynsham Specsavers Limited | Wholesale & retail | 1999 |