| Juniper Recruitment Limited | Professional & scientific | 2022 |
| Juniperhr Ltd | Administrative & support | 2019 |
| Jupiter Foods Ltd | Hospitality | 2023 |
| Juscom & Co.Company Limited | Wholesale & retail | 2023 |
| Just Because Club Ltd | Wholesale & retail | 2025 |
| Just Carer Ltd | Health & social care | 2021 |
| Just Chilling Limited | Manufacturing | 2005 |
| Just Clean Windows Ltd | Administrative & support | 2020 |
| Just for FUN Holiday Club Ltd | Education | 2018 |
| Just Jago LLP | | 2022 |
| Just ROW With IT Limited | Arts & recreation | 2024 |
| Just Transport Limited | Transport & logistics | 2021 |
| Just Window Cleaning Ltd | Administrative & support | 2026 |
| Just Wright Ltd | Construction | 2021 |
| Just Yummy Food Ltd | Hospitality | 2024 |
| Justaskus Limited | Real estate | 2017 |
| Justelec Limited | Construction | 2015 |
| Justhostme Limited | Information & communication | 2007 |
| Justi's Hair and Beauty Limited | Other services | 2024 |
| Justin Tomlinson Ltd | Administrative & support | 2024 |
| Justyanis Limited | Administrative & support | 2019 |
| JV Mortgage Services Ltd | Financial services | 2013 |
| JV Podiatry Limited | Health & social care | 2025 |
| JVD Consultants and Developments Ltd | Professional & scientific | 2024 |
| JVK Limited | Professional & scientific | 2005 |
| JW & JC Ltd | Manufacturing | 2014 |
| JW Mcdougall Limited | Administrative & support | 1998 |
| JWH IT and Media Services Limited | Information & communication | 2014 |
| JWM Aviation Ltd | Professional & scientific | 2011 |
| JWS Auto Cosmetics Limited | Wholesale & retail | 2024 |
| JYH Cleaning & Management Ltd | Administrative & support | 2024 |
| JYM Ltd | Real estate | 2023 |
| JZ Linen&Laundry Services Ltd | Hospitality | 2023 |
| JZ YAP Healthcare Limited | Health & social care | 2022 |
| K & a Services Limited | Manufacturing | 2007 |
| K & B Carpets & Fitting Limited | Construction | 2013 |
| K & C Home Care Ltd | Health & social care | 2024 |
| K & I Auto Repairs Limited | Wholesale & retail | 2025 |
| K & W Holdings Limited | Financial services | 2019 |
| K and P Hairdressing Ltd | Other services | 2019 |
| K B N Property Limited | Real estate | 2012 |
| K Burn Properties Ltd | Real estate | 2024 |
| K C Petroleum Limited | Wholesale & retail | 2011 |
| K Darkwah Limited | Health & social care | 2021 |
| K J S Retail Limited | Wholesale & retail | 2015 |
| K L R Retail Limited | Wholesale & retail | 2009 |
| K M Brickwork Limited | Construction | 2021 |
| K O Plastering Limited | Construction | 2021 |
| K P Builders (Swindon) Limited | Construction | 2013 |
| K P Shai Ltd | Wholesale & retail | 2019 |
| K P Thomas and Sons UK Trading Ltd | Wholesale & retail | 2021 |
| K R H Groundwork Ltd | Construction | 2024 |
| K R M Pandey and Partners Ltd | Other services | 2019 |
| K S Horwood Limited | Administrative & support | 2017 |
| K Telecoms Limited | Information & communication | 2022 |
| K V Accountancy Ltd | Professional & scientific | 2015 |
| K&D Luxury Brands Ltd | Wholesale & retail | 2021 |
| K&D Partnership Limited | Real estate | 2022 |
| K&E Perfect Cleaning Limited | Administrative & support | 2024 |
| K&M Roofing Ltd | Construction | 2023 |
| K&N Travel Associates Limited | Professional & scientific | 2018 |
| K&S Health Solutions Limited | Professional & scientific | 2025 |
| K&V Carpentry and Shopfitting Ltd | Construction | 2024 |
| K. a. M. Systems Limited | Information & communication | 2000 |
| K. Penny Safety Consultancy Ltd | Professional & scientific | 2019 |
| K.Diamini UK Construction Limited | Construction | 2017 |
| K.I.F Scaffolding Ltd | Construction | 2025 |
| K.I.N. (Wilts) Limited | Transport & logistics | 2014 |
| K.J. Crawford Limited | Construction | 2010 |
| K.L.F. Fabrication Limited | Construction | 2012 |
| K.M.S Bricklaying and Groundworks Ltd | Construction | 2020 |
| K2 Logistics (K2L) Ltd | Transport & logistics | 2021 |
| K2 Property Rentals Ltd | Real estate | 2017 |
| K2 Technology Solutions Limited | Information & communication | 2008 |
| K4 Assets UK Limited | Real estate | 2021 |
| K8 Engineering Limited | Professional & scientific | 2012 |
| K8T Consultancy Ltd | Information & communication | 2024 |
| K9CONFIDENTIAL Ltd | Information & communication | 2025 |
| KA & KI Bath Limited | Health & social care | 2025 |
| KA Boutique Ltd | Professional & scientific | 2024 |
| KA Driving Academy Ltd | Education | 2025 |
| KA Group Limited | Real estate | 2020 |
| KA Security Limited | Administrative & support | 2025 |
| KA Ying Limited | Professional & scientific | 2026 |
| KAB Rider Limited | Administrative & support | 2026 |
| KAB Taxis Limited | Transport & logistics | 2002 |
| Kabba & Sons Limited | Real estate | 2022 |
| KAD Transconnect Ltd | Information & communication | 2025 |
| Kadam Care Services Ltd. | Wholesale & retail | 2020 |
| Kafmedia Limited | Extraterritorial | 2007 |
| KAH Associates Ltd | Other services | 2019 |
| KAI Davenport Ltd | Information & communication | 2018 |
| Kaipa's Private Limited | Real estate | 2021 |
| Kaiser Medical Technology Europe Limited | Health & social care | 2020 |
| Kaiser Medical Technology Limited | Health & social care | 2008 |
| Kajani.M Optometrist Limited | Health & social care | 2022 |
| Kakkar Estates Limited | Real estate | 2022 |
| Kalahari Sands UK Ltd | Arts & recreation | 2023 |
| Kali Cares Ltd | Health & social care | 2020 |
| Kaliber Ltd. | Manufacturing | 1996 |