| Johnson Autoworks Ltd | Wholesale & retail | 2015 |
| Johnson James Day Centre Ltd | Real estate | 2020 |
| Johnson Physio Limited | Health & social care | 2026 |
| Johnsons Retail Butchers Limited | Wholesale & retail | 2011 |
| Johnunwin Ltd | Wholesale & retail | 2026 |
| Joint Electrical Services Limited | Other services | 2008 |
| Jokerjay Ltd | Information & communication | 2026 |
| Jolanda Aucott Art Ltd | Arts & recreation | 2023 |
| JON Hollingworth International Ltd | Transport & logistics | 2024 |
| JON Houses Limited | Real estate | 2025 |
| Jones Cloud Services and Consulting Ltd | Information & communication | 2025 |
| Jonken Ltd | Wholesale & retail | 2021 |
| Jonnys Pizza Ltd | Hospitality | 2023 |
| Joogoos Ltd | Information & communication | 2025 |
| Joseph AGU Nutrition Consultant Limited | Health & social care | 2014 |
| Josh Associates Ltd | Professional & scientific | 2017 |
| Joshua Real Estate Ltd | Real estate | 2025 |
| Joulefusion Limited | Extraterritorial | 2011 |
| Jozua Limited | Information & communication | 2021 |
| JR Architecture Limited | Information & communication | 2006 |
| JR K & L Properties Limited | Real estate | 2014 |
| JRL Engineering Limited | Extraterritorial | 2018 |
| Jroc Construction Limited | Construction | 2014 |
| JRR Consulting Ltd | Information & communication | 2023 |
| JRT Coms Limited | Information & communication | 2017 |
| JS Removals Services Limited | Construction | 2022 |
| JSE Electrical Systems Limited | Construction | 2010 |
| JSP Wholesale & Retail Ltd | Wholesale & retail | 2023 |
| JST Corporation Group Ltd | Financial services | 2026 |
| JSW Leicester Ltd | Professional & scientific | 2019 |
| JT Consulting (Midlands) Limited | Professional & scientific | 2015 |
| JT Financial Consultants Limited | Financial services | 2015 |
| JTL Automotive Ltd | Professional & scientific | 2012 |
| JTS Services(Midlands) Ltd | Wholesale & retail | 2019 |
| Juah Rutherford Ltd | Professional & scientific | 2013 |
| Jubb UK Group Limited | Financial services | 2025 |
| Jubilate Hymns Limited | Administrative & support | 1980 |
| Jubilee Motor Services Limited | Wholesale & retail | 2016 |
| Jubilee Sales and Lettings Limited | Real estate | 2021 |
| Judy Blink Ltd. | Education | 2015 |
| Juerschik Properties Ltd | Real estate | 2024 |
| Julia Bates HR Limited | Professional & scientific | 2022 |
| Julia Jones H.R. Limited | Professional & scientific | 2005 |
| Julian Francis Ltd | Water & waste | 2025 |
| Julie K Brown Limited | Extraterritorial | 2011 |
| Juliette Ridewood Limited | Administrative & support | 1993 |
| Julitec Ltd | Wholesale & retail | 2025 |
| Jump Ahead Children's Occupational Therapy Limited | Health & social care | 2013 |
| Junction 23 Lorry Park Limited | Other services | 1987 |
| Juno Golf Ltd | Education | 2024 |
| Juno Simulators CIC | Education | 2025 |
| Jupeton Limited | Construction | 2012 |
| Just Another Cookie Ltd | Hospitality | 2023 |
| Just Another Week Ltd | Wholesale & retail | 2023 |
| Just Custom Limited | Manufacturing | 2025 |
| Just Initials Limited | Manufacturing | 2023 |
| Just Wood Leicestershire C.I.C. | Water & waste | 2012 |
| Justbirthdays Ltd | Information & communication | 2025 |
| Justin Arthur Ltd | Information & communication | 2021 |
| Justin Ward Limited | Professional & scientific | 2003 |
| Justine Albert Limited | Arts & recreation | 2024 |
| JVP Capital Ltd | Financial services | 2025 |
| JW Track Limited | Arts & recreation | 2022 |
| JWB Associates Limited | Professional & scientific | 2022 |
| Jwok Tech Ltd | Information & communication | 2026 |
| K B Electrical Solutions Limited | Manufacturing | 2009 |
| K Barber Design Ltd | Professional & scientific | 2020 |
| K C Automation Limited | Manufacturing | 2011 |
| K D Property Developments Limited | Real estate | 2020 |
| K D Wigmore Building and Joinery Limited | Administrative & support | 2019 |
| K J Greenwell Limited | Professional & scientific | 2010 |
| K Molloy Properties Ltd | Real estate | 2024 |
| K Whittingham Limited | Professional & scientific | 2022 |
| K&A O'Brien Ltd | Professional & scientific | 1999 |
| K&P Insulations Ltd | Construction | 2024 |
| K. Mitchell Memorials Limited | Construction | 2003 |
| K.I.S. Solutions Ltd | Professional & scientific | 2024 |
| K.K.W. Enterprises Limited | Hospitality | 1969 |
| K.M Roofing and Property Maintenance Limited | Construction | 2024 |
| Kaahl Consulting Limited | Professional & scientific | 2016 |
| Kaahl Investments Limited | Financial services | 2018 |
| Kabuki Hairdressing Ltd | Other services | 2015 |
| KAD Investments Limited | Real estate | 2020 |
| KAD Trading Ltd | Wholesale & retail | 2026 |
| Kaebol Technologies Limited | Information & communication | 2014 |
| Kaiserwerk Limited | Information & communication | 2026 |
| Kaleidoscope Party Limited | Extraterritorial | 2014 |
| Kalemore Ltd | Health & social care | 2007 |
| Kalye Sugba Ltd | Hospitality | 2022 |
| Kamps Property Ltd | Real estate | 2018 |
| Kandeep Property Holdings Limited | Real estate | 2016 |
| Kandy and Shakes Ltd | Wholesale & retail | 2026 |
| Kandys News Ltd | Wholesale & retail | 2016 |
| Kanso Properties Limited | Real estate | 2019 |
| Karen Brereton Medical Aesthetics Limited | Health & social care | 2022 |
| Karen Burgin Ltd | Professional & scientific | 2018 |
| Karibani Limited | Education | 2023 |
| Karim's Sons Ltd | Wholesale & retail | 2025 |
| Karl Noble Carpentry Limited | Construction | 2023 |
| Karrie's Pole & Aerial Ltd | Arts & recreation | 2019 |