| June & Hannah Design Limited | Wholesale & retail | 2024 |
| Just Beauty by Jess Bridge Ltd | Other services | 2025 |
| Just Flexi Ltd | Wholesale & retail | 2013 |
| Just Mortgages (South East) Limited | Financial services | 2001 |
| Just the Usual Ltd | Wholesale & retail | 2012 |
| Just-In Case U Limited | Health & social care | 2012 |
| Justcare Service Limited | Health & social care | 2021 |
| Justmichaelak Studios Ltd | Manufacturing | 2020 |
| Justpride Limited | Wholesale & retail | 2019 |
| Juvo AI Ltd | Information & communication | 2026 |
| Juwaf Limited | Administrative & support | 2024 |
| Juyi Calton Ltd | Wholesale & retail | 2025 |
| JV Fit Ltd | Health & social care | 2020 |
| Jvib Ltd | Construction | 2025 |
| JW Consult Project Management Limited | Professional & scientific | 2008 |
| JW Property Consultants Ltd | Real estate | 2021 |
| JW Property Maintenance Limited | Construction | 2002 |
| Jydo's Limited | Other services | 2014 |
| JZ Property Care UK Ltd | Administrative & support | 2026 |
| K & K Pula Marine Limited | Transport & logistics | 2011 |
| K & L Hospitality Limited | Hospitality | 2026 |
| K & M Auto Services Ltd | Wholesale & retail | 2024 |
| K & R Nour Limited | Hospitality | 2024 |
| K and a Interiors Ltd | Construction | 2005 |
| K and a Building Surveyors Ltd | Professional & scientific | 2020 |
| K and K Technologies Limited | Extraterritorial | 2023 |
| K C Nare Ltd | Health & social care | 2013 |
| K L Contracts Ltd | Professional & scientific | 2019 |
| K&A Entertainment Limited | Administrative & support | 2025 |
| K&C Limited | Households | 2025 |
| K&Q Real Estate Investment Ltd | Real estate | 2025 |
| K-Bec Contractors Ltd | Construction | 2019 |
| K28 Developments Ltd | Real estate | 2022 |
| K28 Holdings Ltd | Real estate | 2026 |
| K5 Care Limited | Health & social care | 2025 |
| Kaakt Venture Ltd | Wholesale & retail | 2026 |
| Kabletel Ltd | Professional & scientific | 2025 |
| Kadeeb Consult Limited | Health & social care | 2021 |
| Kadeeb Homes and Properties Limited | Real estate | 2023 |
| Kadire Limited | Health & social care | 2015 |
| Kaffys Kitchen Ltd | Hospitality | 2025 |
| Kaiben Global Logistics Ltd | Transport & logistics | 2025 |
| Kaizen Family Ltd | Extraterritorial | 2023 |
| Kaizhong Trading Limited | Wholesale & retail | 2026 |
| Kajola Foods Ltd | Wholesale & retail | 2022 |
| Kalar Solutions Ltd | Health & social care | 2025 |
| Kaler Engineering Limited | Manufacturing | 2000 |
| Kalev Homes Limited | Real estate | 2024 |
| Kalimatu-Llah Islamic Society UK Limited | Other services | 2014 |
| Kalta Consulting Ltd | Professional & scientific | 2017 |
| Kalyx Beyond Limited | Wholesale & retail | 2020 |
| Kama Property Ltd | Real estate | 2024 |
| Kamara Traffic Ltd | Construction | 2023 |
| Kamernest Ltd | Hospitality | 2020 |
| Kanams Ltd | Wholesale & retail | 2021 |
| Kanani Pharmacy Ltd | Health & social care | 2010 |
| Kanbanchi Ltd | Information & communication | 2016 |
| Kankei Studio Limited | Professional & scientific | 2024 |
| Kappo Property and Consultancy Ltd | Professional & scientific | 2024 |
| Kaps Consultancy Ltd | Professional & scientific | 2012 |
| Kapulus Ltd | Wholesale & retail | 2023 |
| Karecard Solutions UK Limited | Wholesale & retail | 2012 |
| Karinabeautyhub Ltd | Other services | 2024 |
| Karinter Ltd | Real estate | 2022 |
| Karma Motives Ltd | Arts & recreation | 2020 |
| Karmar Security Limited | Administrative & support | 2014 |
| Karmokar Ltd | Real estate | 2021 |
| Karunadina Anivasi Hindugala Okkoota | Education | 2019 |
| KAS Business Services Limited | Professional & scientific | 2021 |
| Kashmere Health Ltd | Health & social care | 2026 |
| Katakyie AS One Limited | Wholesale & retail | 2026 |
| Katalia Ltd | Construction | 2019 |
| Kate Matthews Solutions Ltd | Administrative & support | 2010 |
| Katherine Grice Associates Ltd | Other services | 2014 |
| Katt Solutions Limited | Construction | 2024 |
| Kaur Pizza Express Limited | Wholesale & retail | 2026 |
| KAV Couriers Ltd | Transport & logistics | 2019 |
| Kavinshanaya Limited | Real estate | 2025 |
| KAY Property Management and Maintenance Limited | Construction | 2013 |
| Kayan Enterprise UK Ltd | Wholesale & retail | 2014 |
| KAYCEE222&CO Ltd | Transport & logistics | 2024 |
| Kaynoch Group Ltd | Real estate | 2020 |
| Kays Consultant Limited | Construction | 2013 |
| Kayteehouse Ltd | Wholesale & retail | 2019 |
| Kaytriplej Limited | Health & social care | 2019 |
| Kayus (UK) Services Ltd | Manufacturing | 2013 |
| Kazz Home Improvement Limited | Construction | 2026 |
| KB Commerce Ltd | Wholesale & retail | 2025 |
| KB Express Ltd | Transport & logistics | 2026 |
| KB Motors Group Ltd | Wholesale & retail | 2020 |
| Kbeams Limited | Hospitality | 2025 |
| KBK African Cuisine Limited | Hospitality | 2026 |
| KBK Foods Ltd | Manufacturing | 2026 |
| KBK Secured Ltd | Administrative & support | 2023 |
| KBP Estates Ltd | Real estate | 2017 |
| KCH Facilities Ltd | Construction | 2024 |
| KCT Power Limited | Professional & scientific | 2007 |
| KD Cleaning Ltd | Administrative & support | 2006 |
| Kd&O Brickwork & Construction Ltd | Construction | 2021 |
| Kd&O Steel Ltd | Other services | 2024 |