| JP Perse Way Ltd | Real estate | 2025 |
| JP Watkiss Developments Ltd | Construction | 2019 |
| Jp-Qre Ltd | Information & communication | 2016 |
| JP5 Perse Way Ltd | Real estate | 2025 |
| JP5 Real Estate (Holdings) Ltd | Financial services | 2025 |
| JPC Composites Ltd | Manufacturing | 2018 |
| JPC Musical Promotions Ltd | Arts & recreation | 2026 |
| JPH Technology Limited | Professional & scientific | 2009 |
| Jpros Automation Ltd | Information & communication | 2025 |
| JPS Installs Ltd | Transport & logistics | 2009 |
| Jpsd Medical Ltd | Real estate | 2013 |
| Jpspc Repair Ltd | Other services | 2010 |
| JR Crane Services Ltd | Construction | 2010 |
| JR Executive Transfer Ltd | Transport & logistics | 2023 |
| JR Food Services Ltd | Wholesale & retail | 2020 |
| JRA ACC Limited | Information & communication | 2026 |
| JRA Education Limited | Education | 2025 |
| Jray Services Limited | Professional & scientific | 2024 |
| JRC Investments Limited | Professional & scientific | 2003 |
| JRC Wealth Management Limited | Administrative & support | 2014 |
| JRD Industrial Limited | Extraterritorial | 2013 |
| JRG Windows Ltd | Construction | 2018 |
| JRK Composite Ltd | Manufacturing | 2023 |
| JRS Custom Designs Limited | Wholesale & retail | 2020 |
| JRS Electronics Ltd | Professional & scientific | 2011 |
| JS Exhaust Industries Co. Ltd | Wholesale & retail | 2014 |
| JS Sports & Education Ltd | Education | 2023 |
| JS Vehicle Wraps UK Ltd | Other services | 2025 |
| JS Wilson & SON (Bookbinders) Limited | Manufacturing | 2007 |
| JSB Autos Ltd | Wholesale & retail | 2023 |
| Jsen Plastic Trade Co., Ltd | Administrative & support | 2015 |
| JSG Exotic Foods Cams Limited | Wholesale & retail | 2022 |
| JSI Renovations Ltd | Real estate | 2025 |
| JSL Electrical Services Ltd | Construction | 2013 |
| JSL INVESTMENTS1985 Ltd | Real estate | 2023 |
| JSM Contractors Ltd | Construction | 2016 |
| Jspm Enterprises Limited | Manufacturing | 2024 |
| JST Int'L Ltd | Wholesale & retail | 2019 |
| JT Accommodation Specialists Ltd | Hospitality | 2023 |
| JT Care Solutions Ltd | Health & social care | 2016 |
| Jtap Properties Ltd | Hospitality | 2023 |
| JTC Electrical Services Limited | Professional & scientific | 2018 |
| Jtds Property Management Limited | Real estate | 2024 |
| JTS Trade Limited | Wholesale & retail | 2025 |
| JTT Composites Ltd | Manufacturing | 2018 |
| Ju-Ju Business Consultancy UK Limited | Administrative & support | 2011 |
| Juagoods Limited | Wholesale & retail | 2025 |
| Jubao LAI Ltd | Administrative & support | 2025 |
| Jubilee Centre (Cambridge) | Information & communication | 2010 |
| Jubilee Cottage Limited | Construction | 2020 |
| Jubilee House Limited | Professional & scientific | 2012 |
| Jubilee Prime Trading Limited | Wholesale & retail | 2025 |
| Judd Rentals Ltd | Real estate | 2025 |
| Judith Lennox Ltd. | Arts & recreation | 2011 |
| Judson Consultancy International Ltd | Professional & scientific | 2022 |
| Juelun Trading Co., Ltd | Other services | 2021 |
| Juic'It UP Limited | Hospitality | 2023 |
| Juicy Fruits Model Makers Limited | Arts & recreation | 2008 |
| Jules' Cupboard Ltd | Wholesale & retail | 2026 |
| Julie Brown HR Consultancy Ltd | Administrative & support | 2024 |
| Julorne Flat Management Company Limited | Households | 1978 |
| July Home Co., Ltd | Administrative & support | 2021 |
| Jumbana Cocker Spaniel Ltd | Agriculture & fishing | 2020 |
| Jumbana Dachshund Ltd | Agriculture & fishing | 2020 |
| Jump Networks Ltd | Information & communication | 2002 |
| JUN MUN Ltd | Hospitality | 2025 |
| Junction CDC Limited | Arts & recreation | 1988 |
| June UK Bidco Limited | Financial services | 2020 |
| June UK Finco Limited | Financial services | 2020 |
| June UK Midco Limited | Financial services | 2020 |
| Juneberry Ltd | Administrative & support | 2013 |
| Jungle Treasure Import & Export Co., Ltd | Wholesale & retail | 2023 |
| Junru Smoking Co., Ltd | Wholesale & retail | 2023 |
| Junshi Import and Export Co., Ltd | Wholesale & retail | 2025 |
| Jupiter Express Trading Company Ltd | Wholesale & retail | 2024 |
| Juris Angliae Scientia Limited | Education | 1991 |
| Just Active Ltd | Information & communication | 2025 |
| Just ALL Pro Trades Ltd | Administrative & support | 2025 |
| Just Clean Cambridge Ltd | Administrative & support | 2020 |
| Just Garage Ltd | Wholesale & retail | 2014 |
| Just in Time Publishing Ltd | Information & communication | 2016 |
| Just Mobile Games Limited | Information & communication | 2004 |
| Just Padel Cambridge Ltd | Arts & recreation | 2026 |
| Just Recruitment Solutions Limited | Administrative & support | 2015 |
| Just Roofing Solutions Ltd | Construction | 2026 |
| Just Sofas Limited | Wholesale & retail | 2005 |
| Just Wrong Ltd | Wholesale & retail | 2015 |
| Justice Education Network Limited | Education | 2017 |
| Justicesure Ltd | Information & communication | 2025 |
| Justin Paget Photography Ltd | Professional & scientific | 2012 |
| Justin Yates Electrical Limited | Construction | 2018 |
| Justwontdie Ltd | Information & communication | 2019 |
| Juxin Media Co., Ltd. | Wholesale & retail | 2025 |
| JV Dining Ltd | Real estate | 2021 |
| JVC Trading Limited | Wholesale & retail | 2013 |
| JW & Co. Accountancy Ltd | Professional & scientific | 2014 |
| JW Cambridge Ltd | Wholesale & retail | 2024 |
| JW Edit Ltd | Information & communication | 2006 |
| JW Fulfillment UK Limited | Transport & logistics | 2025 |
| JW Insight Limited | Professional & scientific | 2025 |