| JAC Security Limited | Professional & scientific | 2017 |
| Jackdarlin Ltd | Arts & recreation | 2025 |
| Jade Xinyi Limited | Hospitality | 2023 |
| JAL Fish Bar Ltd | Hospitality | 2023 |
| James Consulting (Derbyshire) Ltd | Professional & scientific | 2025 |
| James Shaw Sports Promotions Limited | Arts & recreation | 2019 |
| Jameson & Crown Limited | Construction | 1990 |
| JAP (Higham) Services Ltd | Transport & logistics | 2025 |
| Jay's Tanning Limited | Arts & recreation | 2004 |
| JBD Media Ltd | Information & communication | 2019 |
| JCT 28 Limited | Wholesale & retail | 1990 |
| JD Custom Refinishes Ltd | Wholesale & retail | 2022 |
| Jdmorgan Trading Limited | Wholesale & retail | 2024 |
| Jduk Investments Limited | Professional & scientific | 2012 |
| Jean Holder Ltd | Hospitality | 2018 |
| Jeffryes Consulting Limited | Information & communication | 2022 |
| Jeffryes Digital Health Limited | Information & communication | 2025 |
| JEM Transport Ltd | Transport & logistics | 2002 |
| Jenn Properties Ltd | Real estate | 2026 |
| Jenner-Dyer Holdings Limited | Arts & recreation | 2016 |
| Jerram Investment Properties Limited | Construction | 2024 |
| Jezyk Ltd | Wholesale & retail | 2024 |
| JF Modelling Limited | Other services | 2024 |
| JFJ Property Ltd | Real estate | 2024 |
| JJ Commercial Construction Ltd | Construction | 2011 |
| JJ Commercial Properties Ltd | Real estate | 2026 |
| JL Estate Management Ltd | Manufacturing | 2023 |
| JL Strategic Services Ltd | Professional & scientific | 2025 |
| JLH Property Experts Ltd | Real estate | 2016 |
| JM Smith Properties Ltd | Extraterritorial | 2015 |
| JME Electrical (North West) Limited | Construction | 2016 |
| JME Electrical Ltd | Construction | 2025 |
| JME Estates Limited | Real estate | 2021 |
| JMT Midlands Ltd | Administrative & support | 2018 |
| JO Robinson Legal Ltd | Professional & scientific | 2026 |
| JOE Brown Contractors Limited | Construction | 2003 |
| John and SON Transport Ltd | Transport & logistics | 2026 |
| Jools Reserve Limited | Manufacturing | 2026 |
| JP Management & Productions Ltd | Professional & scientific | 2026 |
| JP Perkins Properties Ltd | Real estate | 2021 |
| JP Treeworks Ltd | Administrative & support | 2025 |
| JPB Housing Ltd | Real estate | 2020 |
| JRS Sales and Marketing Limited | Professional & scientific | 2025 |
| JTG Leisure Limited | Hospitality | 2023 |
| Jubilee Group Ltd | Real estate | 2003 |
| Judge Textile Cutting Company Limited | Manufacturing | 2003 |
| Just Alloys Ltd | Wholesale & retail | 2014 |
| Just Bandits Limited | Wholesale & retail | 2003 |
| Just Perfect Gifts Ltd | Wholesale & retail | 2021 |
| Justin Heaton Limited | Financial services | 2002 |
| Juventa 4 Care Ltd | Health & social care | 2010 |
| Juventa Services Ltd | Real estate | 2023 |
| K & S (Tibshelf) LLP | | 2023 |
| K R Consultancy Services Ltd | Professional & scientific | 2025 |
| K&J Drywall Solutions Ltd | Construction | 2017 |
| K&M Ryde Transport Limited | Transport & logistics | 2021 |
| K75 Properties Ltd | Real estate | 2019 |
| KA MID Co Ltd | Financial services | 2025 |
| KAB Build Ltd | Construction | 2022 |
| Kaizen ERP Ltd | Information & communication | 2023 |
| KAL Tire (UK) Limited | Mining & quarrying | 1977 |
| KAL Tire Southern African Holdings Limited | Professional & scientific | 2011 |
| KAS Energy Ltd | Construction | 2020 |
| Kattou Co Ltd | Real estate | 2025 |
| KB OT Therapy Services Ltd | Health & social care | 2022 |
| KB WF Ltd | Wholesale & retail | 2025 |
| Kcsa Cleaning Ltd | Administrative & support | 2023 |
| KCY Aesthetics Ltd | Other services | 2026 |
| Keane Logistics Ltd | Transport & logistics | 2024 |
| Keeling Environmental Ltd | Professional & scientific | 2025 |
| Keeptake Ltd | Wholesale & retail | 2021 |
| Kejis Food & Snacks Limited | Hospitality | 2025 |
| Keljay Limited | Manufacturing | 1997 |
| Keljay Manufacturing Limited | Professional & scientific | 2005 |
| Keljay Rentals Ltd | Manufacturing | 2025 |
| Keljay Technical Services Ltd | Extraterritorial | 2019 |
| Kelly Family Holdings Ltd | Construction | 2024 |
| Kelly Jowett Art and Consultancy Ltd | Wholesale & retail | 2025 |
| Kenley Home Improvements Ltd | Wholesale & retail | 2026 |
| Kent Building Plastics (UK) Ltd. | Extraterritorial | 1998 |
| KER Accountancy Ltd. | Professional & scientific | 2013 |
| Keramikos Limited | Manufacturing | 1992 |
| Kevin Bunting Haulage Limited | Transport & logistics | 2011 |
| Keyhole IT Solutions Ltd | Other services | 2020 |
| KG ENG Limited | Manufacturing | 2018 |
| Kiak London Ltd | Wholesale & retail | 2007 |
| Kicon Ltd | Construction | 2025 |
| Kinetic Sound Engineering Ltd | Information & communication | 2025 |
| King Defence Limited | Manufacturing | 2025 |
| King Highway Products Limited | Manufacturing | 2001 |
| King Rail Limited | Construction | 2025 |
| King Trailers Limited | Manufacturing | 1998 |
| King Transport Equipment Limited | Professional & scientific | 2006 |
| King Vehicle Engineering Limited | Professional & scientific | 2005 |
| King Vehicle Rental Limited | Administrative & support | 2025 |
| Kingdom Christian School | Education | 2016 |
| Kings Owen (Derbyshire) Ltd | Professional & scientific | 2022 |
| Kiragu London Ltd | Health & social care | 2018 |
| Kith & Kilderkin Ltd | Hospitality | 2023 |
| KLC Inflatables Ltd | Manufacturing | 2026 |