| Jsdhanda Properties Ltd | Real estate | 2025 |
| JSG Block Management Ltd | Households | 2021 |
| JSG Contractors Ltd | Construction | 2014 |
| JSH Estates Limited | Real estate | 2020 |
| Jshree Investment Limited | Real estate | 2021 |
| Jshree Retail Limited | Wholesale & retail | 2016 |
| JSK Designs Ltd | Construction | 2023 |
| JSK Plumbing & Heating Ltd | Construction | 2026 |
| JSK Real Estates Limited | Real estate | 2020 |
| JSL Osteopathy Ltd | Health & social care | 2022 |
| JSR99 Ltd | Wholesale & retail | 2025 |
| JSS Property Management Ltd | Real estate | 2022 |
| Jstu Limited | Information & communication | 2018 |
| JT Estates Services Ltd | Real estate | 2026 |
| JT Properties & Investments Ltd | Real estate | 2023 |
| JT Properties Management Ltd | Real estate | 2023 |
| JTC BMS Services Ltd | Construction | 2025 |
| JTC Group of Companies Ltd | Financial services | 2026 |
| JTC Welding & Engineering Ltd | Professional & scientific | 2019 |
| Jtcogs Ltd | Transport & logistics | 2026 |
| JTM Civils Limited | Construction | 2026 |
| Jubilee Court (High Wycombe) Residents Company Limited | Real estate | 1988 |
| Juice Resource Solutions Ltd | Administrative & support | 2006 |
| Juneja Limited | Real estate | 2024 |
| Junior Coders Limited | Information & communication | 2022 |
| Junior Jack Ltd | Construction | 2019 |
| Junior Motors Ltd | Wholesale & retail | 2023 |
| Juniper Hills Limited | Information & communication | 2018 |
| Juniper Horizons Ltd | Information & communication | 2025 |
| Jurrasic Family Ltd | Real estate | 2020 |
| Just 4 Landlords Limited | Financial services | 2015 |
| Just Airports Chauffeur Services Limited | Other services | 1999 |
| Just Lofts Ltd | Construction | 2019 |
| Just Moving Muck Limited | Water & waste | 2025 |
| Juvi Enterprises (UK) Ltd | Wholesale & retail | 2017 |
| Jvan Transport Ltd | Transport & logistics | 2026 |
| Jvee Homes Ltd | Real estate | 2024 |
| Jvox Limited | Information & communication | 2025 |
| JW Roofing (London) Limited | Construction | 2014 |
| JWR Storage Ltd | Transport & logistics | 2026 |
| JYL Biomedical Services Ltd | Public administration | 2022 |
| JYN Properties Ltd | Real estate | 2021 |
| Jyoti Tailors Ltd | Wholesale & retail | 2025 |
| Jyqa Ltd | Professional & scientific | 2024 |
| K Barber Station Ltd | Other services | 2023 |
| K Beauty Skincare Limited | Wholesale & retail | 2019 |
| K C R Aesthetics Ltd | Other services | 2020 |
| K D West Ltd | Construction | 2025 |
| K K Building Contractors Ltd | Construction | 2019 |
| K Martial Arts Limited | Education | 2023 |
| K Mcginnes Ltd | Information & communication | 2026 |
| K Mills Limited | Financial services | 2019 |
| K P Management Consultancy Ltd | Professional & scientific | 2014 |
| K R D Ltd | Wholesale & retail | 2015 |
| K Sidhu Transport Ltd | Transport & logistics | 2026 |
| K Wrap Customs Ltd | Wholesale & retail | 2020 |
| K&D Asset Management Limited | Real estate | 2020 |
| K&G Tyre Services Ltd | Wholesale & retail | 2022 |
| K&K Trading Ltd | Wholesale & retail | 2023 |
| K&L Logistics Ltd | Transport & logistics | 2025 |
| K&L Rentals Ltd | Administrative & support | 2023 |
| K-Utiful Limited | Wholesale & retail | 2023 |
| K.B Scaffolding (UK) Ltd | Construction | 2013 |
| K.C.Y. Catering Limited | Hospitality | 2022 |
| K.D.K Global Air Ltd | Wholesale & retail | 2022 |
| K.Maria Ltd | Wholesale & retail | 2021 |
| K9 Adventures Ltd | Other services | 2019 |
| KA Residential Investment Management Ltd | Real estate | 2022 |
| Kabaddi Sport Club Southall Ltd | Education | 2022 |
| Kabbb Limited | Wholesale & retail | 2025 |
| Kacheto 1 Ltd | Construction | 2022 |
| Kada Technologies Limited | Administrative & support | 2023 |
| Kadecore Ltd | Hospitality | 2026 |
| Kadefy Ltd | Information & communication | 2025 |
| Kadera Medical Services Ltd | Health & social care | 2011 |
| Kadiri Financial Services Ltd | Financial services | 2025 |
| Kahawicks Properties Ltd | Real estate | 2024 |
| Kaher Properties Limited | Real estate | 2019 |
| Kahlon Investments Ltd | Real estate | 2019 |
| KAI Odontology Limited | Health & social care | 2019 |
| Kaiizen Limited | Wholesale & retail | 2022 |
| Kaizenteq Investments Ltd | Real estate | 2024 |
| Kaizenteq Ltd | Information & communication | 2023 |
| Kaja Fashion Design Limited | Professional & scientific | 2012 |
| Kakkar Enterprises Limited | Wholesale & retail | 2025 |
| Kalidora and Company Limited | Manufacturing | 2026 |
| Kaloty Ltd | Real estate | 2019 |
| Kalpaka Limited | Health & social care | 2023 |
| Kalsi Family LLP | | 2017 |
| Kalsi Holdings Ltd | Real estate | 2017 |
| Kalsi UK Developments Ltd | Real estate | 2019 |
| Kalsi UK Investments Ltd | Real estate | 2015 |
| Kalyug Couture Ltd | Wholesale & retail | 2025 |
| KAM ENG Services Ltd | Professional & scientific | 2014 |
| KAM Properties Ltd | Real estate | 2018 |
| KAM Woodstone Ltd | Manufacturing | 2026 |
| Kamal Motors Ltd | Wholesale & retail | 2016 |
| Kamboj Associates Limited | Professional & scientific | 1996 |
| Kamboj Transport Ltd | Transport & logistics | 2025 |
| Kamdhenu Limited | Wholesale & retail | 2011 |