| K Costas Estates Ltd | Real estate | 2025 |
| K J Cook Engineering Limited | Manufacturing | 2007 |
| K K WAT (UK) Limited | Real estate | 2022 |
| K Mcfarlane Solutions Ltd | Professional & scientific | 2020 |
| K Nelson & Company Limited | Real estate | 2016 |
| K O Private Practice Limited | Health & social care | 2021 |
| K W Projects Limited | Professional & scientific | 2002 |
| K&F Kent Limited | Real estate | 2023 |
| K&M UK Investments Ltd | Real estate | 2014 |
| K&T Electromech Services Limited | Energy | 2020 |
| K. Watson VPM Ltd | Professional & scientific | 2022 |
| K.D. Sons Limited | Information & communication | 2025 |
| K.J. Collins & Associates Ltd | Wholesale & retail | 2002 |
| K.Wess Trims and Travel Ltd | Transport & logistics | 2023 |
| K3 Commercial Limited | Construction | 2012 |
| KA (Keston) Ltd | Hospitality | 2025 |
| Kaan Fish and Chips Limited | Hospitality | 2016 |
| Kabod Ltd | Administrative & support | 2022 |
| Kaellise Ltd | Professional & scientific | 2022 |
| Kaellise Properties Ltd | Real estate | 2026 |
| Kaizen Media Group Ltd | Professional & scientific | 2026 |
| Kaizer Motor Ltd | Wholesale & retail | 2014 |
| Kaizer Property Management Ltd | Real estate | 2019 |
| Kamertonix Ltd | Information & communication | 2026 |
| Kamilos Electrical Services Ltd | Construction | 2016 |
| Kandtems Ltd | Construction | 2023 |
| Kane Plumbing and Heating Ltd | Construction | 2019 |
| Kanive Ventures Limited | Information & communication | 2023 |
| Kaptius Holdings Limited | Financial services | 2025 |
| KAR Professional Cleaning Limited | Administrative & support | 2025 |
| Karban Limited | Construction | 2025 |
| Karim Dental Ltd | Health & social care | 2019 |
| Karstutenants' Association Limited | Households | 1961 |
| Karta Properties Ltd | Real estate | 2021 |
| Kashya Ltd | Real estate | 2019 |
| Kaspra Solutions Ltd | Information & communication | 2020 |
| Kastal Limited | Administrative & support | 2009 |
| Kate LDN Ltd | Wholesale & retail | 2019 |
| Kate Wiltshire Ltd | Information & communication | 2021 |
| Katoa Botanicals Ltd | Wholesale & retail | 2023 |
| Kavi Nova Technologies Limited | Manufacturing | 2026 |
| Kaymac Construction Limited | Construction | 1989 |
| Kaymusmammy Consultancy Limited | Health & social care | 2021 |
| Kayteeem Proper-T Solutionz Ltd | Information & communication | 2019 |
| Kazz Ltd | Construction | 2019 |
| KB Electrical South East Ltd | Construction | 2023 |
| KB I Joinery Ltd | Manufacturing | 2021 |
| KB Residential Limited | Real estate | 2022 |
| KBB Consulting Ltd | Other services | 2023 |
| KBS Scaffolding Limited | Construction | 2024 |
| KC Fire & Safety Ltd | Construction | 2025 |
| KCP Perioperative Practitioner Ltd | Health & social care | 2013 |
| Kcsge Holdings Limited | Administrative & support | 2008 |
| Kead Plumbing Services Ltd | Construction | 2024 |
| Keban Ltd | Extraterritorial | 2019 |
| Keep UP Business Ltd | Wholesale & retail | 2025 |
| Keepers Ball Limited | Arts & recreation | 2009 |
| Keepsake Parties Ltd | Arts & recreation | 2025 |
| Keith Withall & Co Limited | Professional & scientific | 2007 |
| Kelen Transport Consulting Limited | Professional & scientific | 2020 |
| Kemson Properties Ltd | Real estate | 2024 |
| Kenan Investments Limited | Real estate | 2020 |
| Kenilworth Estates Management Limited | Extraterritorial | 2006 |
| Kenn Real Estates Ltd | Real estate | 2022 |
| Kennedy & Co (Quantity Surveyors) Limited | Professional & scientific | 1998 |
| Kensington Court (Beckenham) Residents Association Limited | Households | 2006 |
| Kent & County Properties Ltd | Real estate | 2011 |
| Kent & Sussex Garage Doors Limited | Construction | 1989 |
| Kent and Essex Plumbing Heating Services Limited | Construction | 2010 |
| Kent and London Pest Control Ltd | Professional & scientific | 2024 |
| Kent Autohaus Limited | Wholesale & retail | 2025 |
| Kent Building and Renewables Ltd | Construction | 2026 |
| Kent Business Coaching Limited | Administrative & support | 2018 |
| Kent Cancer Clinic Ltd | Health & social care | 2015 |
| Kent Cars Limited | Wholesale & retail | 2026 |
| Kent Comics Limited | Wholesale & retail | 2023 |
| Kent Container Storage Limited | Transport & logistics | 2020 |
| Kent Courier Group Ltd | Transport & logistics | 2025 |
| Kent Environmental Ltd | Construction | 2017 |
| Kent Estimating and Surveying Limited | Professional & scientific | 2013 |
| Kent Property Contracts Limited | Construction | 1994 |
| Kent Sports Podiatry Ltd | Health & social care | 2019 |
| Kent Tennis & Padel Community Ventures Limited | Arts & recreation | 2026 |
| Kent Trade & DIY Ltd | Wholesale & retail | 2023 |
| Kent Tree Care Ltd | Agriculture & fishing | 2006 |
| Kent Underfloor Heating Ltd | Construction | 2026 |
| Kent's Landscapes Ltd | Administrative & support | 2021 |
| Kenthouse Buildings Ltd | Construction | 2025 |
| Kentish Homecare Agency Limited | Health & social care | 2008 |
| Kentish Support Services Limited | Health & social care | 2015 |
| Kenzi Rezi Ltd | Real estate | 2025 |
| Kepi International Solutions Limited | Construction | 2011 |
| Kerri Northcott Limited | Administrative & support | 2019 |
| Keston Couriers Limited | Transport & logistics | 2015 |
| Kestons Executive Cars Ltd | Transport & logistics | 2026 |
| Keswick Court Bromley Limited | Households | 1999 |
| Kevally Limited | Administrative & support | 2002 |
| Kevin Freese & Family (Consultants) Ltd | Professional & scientific | 2002 |
| Key Dynamics London Limited | Wholesale & retail | 2025 |
| Key Master Ltd | Manufacturing | 2026 |