| JC Electrical Plymouth Ltd | Manufacturing | 2022 |
| JC Fire & Security SW Ltd | Administrative & support | 2020 |
| JC Tech Holdings Ltd | Financial services | 2023 |
| JCD Management Limited | Professional & scientific | 2005 |
| Jcet Limited | Construction | 2024 |
| JCK Marine Joinery Ltd | Construction | 2023 |
| JCK Property Management & Services Limited | Construction | 2013 |
| JCL Decor Limited | Construction | 2022 |
| Jcls Management Ltd | Other services | 2017 |
| JCM Automotive Ltd | Wholesale & retail | 2021 |
| JCM Orthopaedic Consulting Ltd | Health & social care | 2026 |
| JCP Food Production Limited | Hospitality | 2025 |
| JCT Power Electrical Ltd | Construction | 2016 |
| Jc’S Coffee Limited | Wholesale & retail | 2026 |
| JD Civil Construction Ltd | Construction | 2025 |
| JD Civil Engineering & Ground Works Ltd | Construction | 2008 |
| JD Civils Plant Ltd | Construction | 2025 |
| JD Electrical Services (SW) Limited | Construction | 2014 |
| JD Interior Solutions (SW) Ltd | Construction | 2024 |
| JD Roofing & Landscaping Ltd | Construction | 2025 |
| JDA Transport Limited | Transport & logistics | 2015 |
| JDC Drivers Ltd | Construction | 2020 |
| JDF Auto Repairs & Recovery Ltd | Wholesale & retail | 2025 |
| JDP 1337 Ltd | Construction | 2020 |
| JDR Farms Ltd. | Agriculture & fishing | 2012 |
| JDY Limited | Professional & scientific | 2016 |
| Jeat Ltd | Information & communication | 2024 |
| JEC (SW) Property Limited | Construction | 2021 |
| JEC Construction Group (Holdings) Limited | Financial services | 2026 |
| JEC Construction Holdings Limited | Financial services | 2026 |
| JEM Projects (Plymouth) Limited | Health & social care | 2012 |
| JEM Scaffolding Holdings 2025 Limited | Financial services | 2025 |
| JEM Scaffolding Holdings Limited | Real estate | 2013 |
| JEM Scaffolding Limited | Construction | 2006 |
| Jenst Limited | Professional & scientific | 2013 |
| Jeremiah's Journey | Health & social care | 2011 |
| Jerrican Ltd | Construction | 2019 |
| Jesse Leach Property Ltd | Hospitality | 2022 |
| Jesus Lives Ltd | Other services | 2019 |
| JET SET Go Safaris Plymouth Ltd | Transport & logistics | 2020 |
| JET Wash Away Ltd | Administrative & support | 2022 |
| JEZ Cram Property Ltd | Households | 2025 |
| JEZ Global Ltd | Health & social care | 2025 |
| JF Oliver Limited | Extraterritorial | 2014 |
| JFE Freeholds Ltd | Real estate | 2018 |
| JFE Properties Ltd | Real estate | 2018 |
| JFL Repowered Limited | Wholesale & retail | 2021 |
| JFM Properties Ltd | Real estate | 2016 |
| JGL Property Limited | Real estate | 2017 |
| JGM Travel Limited | Administrative & support | 2019 |
| JH Ceilings and Partitions Limited | Construction | 2023 |
| JH Cuisines Ltd | Hospitality | 2019 |
| JH Designs Southwest Limited | Administrative & support | 2011 |
| JH Electrical SW Ltd | Construction | 2019 |
| JH Takeaway Ltd | Hospitality | 2021 |
| JHR Construction Limited | Construction | 2016 |
| Jibril Limited | Transport & logistics | 2019 |
| JIK Consultancy Limited | Professional & scientific | 2017 |
| Jillies Ltd | Wholesale & retail | 2025 |
| Jils Leisure Limited | Other services | 2020 |
| JJ Interiors Limited | Construction | 2011 |
| JJ Smith & Co Joinery Ltd | Construction | 2007 |
| Jjbrady Ltd | Real estate | 2018 |
| JJC Recovery Ltd | Transport & logistics | 2022 |
| JJD Management Co Ltd | Hospitality | 2026 |
| Jjerpsl Limited | Wholesale & retail | 2025 |
| JJS Property (SW) Limited | Households | 2022 |
| JJV Electrical Ltd | Construction | 2021 |
| JK Games Ltd | Wholesale & retail | 2025 |
| JKD Group SW Ltd | Professional & scientific | 2025 |
| JKD Healthcare Limited | Health & social care | 2022 |
| JKD Properties SW Ltd | Real estate | 2025 |
| JL Farmer Hydrographic Services Ltd | Professional & scientific | 2022 |
| JL Football Event Management Limited | Public administration | 2026 |
| JL Metalworks Ltd | Manufacturing | 2025 |
| JLA Healthcare Ltd | Health & social care | 2023 |
| JLC Fabrication Ltd | Manufacturing | 2014 |
| JLC Protection Limited | Financial services | 2019 |
| JLD Recruit Ltd | Administrative & support | 2026 |
| JLH Fire Safety Services Ltd | Extraterritorial | 2019 |
| JLM Bricklaying Ltd | Construction | 2021 |
| JLP Contract Limited | Construction | 2023 |
| JLP Estates South West Limited | Real estate | 2023 |
| JLR KR Ltd | Real estate | 2025 |
| JLS B.C.S. Scaffolding Ltd | Construction | 2015 |
| JM Business Services Ltd | Administrative & support | 2018 |
| JM Consultancy Services Ltd | Professional & scientific | 2025 |
| JM Steel Services Ltd | Professional & scientific | 2018 |
| JM Utilities Limited | Construction | 2017 |
| JMC Drain Consultants Limited | Construction | 2025 |
| JMD Holdings (Devon) Limited | Financial services | 2026 |
| JMD Plumbing & Heating SW Ltd | Construction | 2021 |
| JML Analytics Limited | Administrative & support | 2017 |
| JMN SW Ltd | Real estate | 2023 |
| JMP Construction Limited | Construction | 2001 |
| Jmrc Construction Services Ltd | Construction | 2024 |
| Joanna Mikus Ltd | Health & social care | 2009 |
| Jobe Mechanical Services Ltd | Professional & scientific | 2018 |
| Jobel Limited | Construction | 1998 |
| Joce Roofing Limited | Construction | 2016 |