| Jacobs Building Management Company Limited | Households | 2004 |
| Jacobs Wells Road (Bristol) Management Company Limited | Households | 2016 |
| Jacobsen Salg OG Maskin Ltd | Professional & scientific | 2008 |
| Jacqui Porter Consulting Limited | Professional & scientific | 1997 |
| Jacs Property Group Ltd | Real estate | 2025 |
| JACS5 Limited | Financial services | 2025 |
| Jadama Care Service Ltd | Health & social care | 2025 |
| Jadarie Ltd | Wholesale & retail | 2026 |
| Jade Carr-Daley Ltd | Professional & scientific | 2024 |
| Jade Coelho Hair Limited | Other services | 2024 |
| Jade Frog Limited | Wholesale & retail | 2024 |
| Jade Garden Bristol Limited | Hospitality | 2025 |
| Jadecrown Consultancy Limited | Administrative & support | 2017 |
| Jaded Dragon Ltd | Hospitality | 2024 |
| Jadeja Homes Limited | Real estate | 2025 |
| Jadoon Horizon Facilities Limited | Wholesale & retail | 2025 |
| Jadora Empower Ltd | Professional & scientific | 2025 |
| Jafar Management Limited | Hospitality | 2025 |
| Jaff Barbers Shop Ltd | Other services | 2025 |
| Jaff Hand Car Wash Ltd | Administrative & support | 2025 |
| Jaff Mini Market Ltd | Wholesale & retail | 2025 |
| Jaffabuild Ltd | Real estate | 2019 |
| Jafflongmaharaj Ltd | Hospitality | 2025 |
| Jagamana Limited | Wholesale & retail | 2021 |
| Jagjit Ltd | Real estate | 2018 |
| Jago & SON Ltd | Hospitality | 2023 |
| Jago Enterprises Limited | Real estate | 2015 |
| Jago Jake Limited | Financial services | 2017 |
| Jaguar Commissioning Services Limited | Construction | 2017 |
| Jaguar OIL & GAS UK Limited | Administrative & support | 1991 |
| Jaguna Ltd | Hospitality | 2011 |
| Jagware Ltd | Information & communication | 2023 |
| JAH Property Solutions Ltd | Real estate | 2021 |
| Jahmix Ltd | Construction | 2025 |
| JAI & G Properties Ltd | Real estate | 2021 |
| JAI Media Ltd | Information & communication | 2019 |
| Jaiden Takeaway Limited | Hospitality | 2023 |
| Jaina Healthcare Professional Ltd | Health & social care | 2018 |
| Jaishiv Limited | Real estate | 2025 |
| Jake Davis Design Limited | Professional & scientific | 2014 |
| Jake Holcombe Electrical Limited | Construction | 2026 |
| Jake Sparey Productions Ltd | Information & communication | 2025 |
| Jake's Autos Ltd | Wholesale & retail | 2026 |
| Jakescapes Limited | Information & communication | 2026 |
| Jakoby Ltd | Construction | 2013 |
| Jaks Wholesalers Limited | Wholesale & retail | 2020 |
| Jaksystems Ltd | Information & communication | 2022 |
| Jakz Mapz 0117 Limited | Wholesale & retail | 2025 |
| JAL Organisational Solutions Ltd | Professional & scientific | 2014 |
| Jala Minibuses (GB) Ltd | Transport & logistics | 2011 |
| Jalfrezi Software Limited | Information & communication | 2008 |
| Jalia Management Ltd | Professional & scientific | 2026 |
| Jallow Jerry Limited | Health & social care | 2014 |
| Jalr Consulting Services Ltd | Information & communication | 2025 |
| JAM Couriers Services Limited | Transport & logistics | 2016 |
| JAM Motors Ltd | Wholesale & retail | 2023 |
| JAM Nice CIC | Information & communication | 2023 |
| JAM Play Holdings Limited | Administrative & support | 2025 |
| JAM Properties Bristol Ltd | Real estate | 2016 |
| JAM Rugby Ltd | Arts & recreation | 2025 |
| JAM Shack Kitchen Ltd | Hospitality | 2019 |
| Jamaica Street Studios CIC | Arts & recreation | 2005 |
| Jambala Consulting Ltd | Administrative & support | 2024 |
| Jambi Digital Ltd | Information & communication | 2018 |
| Jambridge Holdings Ltd | Financial services | 2025 |
| Jamdaw Property Ltd | Real estate | 2022 |
| Jamdung Kitchen Ltd | Hospitality | 2026 |
| James and Rhia's Ltd | Wholesale & retail | 2020 |
| James Antony Flooring Limited | Wholesale & retail | 2025 |
| James Ball Cars Ltd | Wholesale & retail | 2012 |
| James Bosley Ltd | Construction | 2018 |
| James Boyd Dental Limited | Health & social care | 2023 |
| James Bulk Freight Limited | Transport & logistics | 2015 |
| James Burleigh Holdings Limited | Financial services | 2025 |
| James Cars Limited | Wholesale & retail | 2022 |
| James Cooper AV Ltd | Construction | 2024 |
| James Crumpton Properties Ltd | Real estate | 2023 |
| James Dorman Music Ltd | Arts & recreation | 2006 |
| James Ellis Stevens Limited | Wholesale & retail | 2003 |
| James Gareh Limited | Professional & scientific | 2018 |
| James Gibbings Roofing Limited | Construction | 2021 |
| James Gould Ltd | Wholesale & retail | 2020 |
| James Hendy (Bristol) Limited | Real estate | 1953 |
| James Hunter Consultancy Limited | Professional & scientific | 2022 |
| James Jensen Design Ltd | Professional & scientific | 2016 |
| James Kelvin Developments Ltd | Construction | 2020 |
| James King Photographer Limited | Professional & scientific | 2005 |
| James L.Phillips(Property)Limited | | 1952 |
| James Landscaping & Contracts Limited | Administrative & support | 2014 |
| James Mount Health and Fitness Ltd | Other services | 2017 |
| James Perrott Ltd | Professional & scientific | 2011 |
| James Pickering Ltd | Professional & scientific | 2024 |
| James Pope Dentistry Limited | Health & social care | 2022 |
| James Publications Limited | Wholesale & retail | 2024 |
| James Rail Engineering Limited | Professional & scientific | 2013 |
| James Recruitment Limited | Administrative & support | 2009 |
| James Reed Public Relations Limited | Professional & scientific | 1964 |
| James Ross Healthcare Ltd | Health & social care | 2006 |
| James Ross Investments Limited | Financial services | 2017 |
| James Scott's North Somerset Reuse Project CIC | Wholesale & retail | 2013 |