| J.G.Gilder Limited | Agriculture & fishing | 2018 |
| J.J Edenland Global Ltd | Health & social care | 2023 |
| J.J. Flint Ltd | Real estate | 1993 |
| J.J.S. Construction Limited | Construction | 2000 |
| J.L. Molloy Electrical Services Ltd | Construction | 2011 |
| J.O. Smith Building Company Ltd | Construction | 2008 |
| J.R.S. Securities Limited | Professional & scientific | 1980 |
| J2TECH Limited | Professional & scientific | 2007 |
| J3 Investments Limited | Financial services | 2017 |
| J3M (Powersync) Ltd | Financial services | 2022 |
| J6 Electrical Solutions Ltd | Construction | 2024 |
| JA Build Ltd | Real estate | 2024 |
| Ja-Guy Ltd | Hospitality | 2025 |
| Jabberwocky Day Nursery Limited | Health & social care | 2005 |
| JAC Artistry Limited | Other services | 2017 |
| Jack Bryant Productions Ltd | Administrative & support | 2018 |
| Jack Bryant Projects Ltd | Administrative & support | 2026 |
| Jack Driver Personal Training Ltd | Arts & recreation | 2026 |
| Jack Hall Ltd | Real estate | 2011 |
| Jack'D N Juicy Clothing & Co Ltd | Wholesale & retail | 2022 |
| Jack's Rainbow Limited | Real estate | 2021 |
| Jackdaw Design & Print Limited | Professional & scientific | 2003 |
| Jackie Harris Consultancy Ltd | Professional & scientific | 2022 |
| Jackpot Marketing Ltd | Information & communication | 2018 |
| Jackson Engineering Solutions Limited | Information & communication | 2007 |
| Jackson's Garden Café Limited | Real estate | 2020 |
| Jacksure Ltd | Construction | 2013 |
| Jacob Property Group Ltd | Financial services | 2022 |
| Jacobs and Sons Ltd | Manufacturing | 2012 |
| Jacobs Care Consultancy Limited | Health & social care | 2018 |
| Jacqueline Labbe Creative Solutions Limited | Professional & scientific | 2026 |
| Jacst Group Ltd | Financial services | 2025 |
| Jacst Ltd | Real estate | 2021 |
| Jade Beer Publishing Limited | Information & communication | 2018 |
| Jade Court (Cheltenham) Limited | Households | 1985 |
| Jade Horizon Ventures Limited | Financial services | 2026 |
| JAE Systems Ltd | Information & communication | 2025 |
| Jaez Property Ventures Ltd | Construction | 2025 |
| Jahan Pizza Ltd | Hospitality | 2019 |
| Jai's Thai (Cotswolds) Limited | Hospitality | 2022 |
| Jaigh Ltd | Arts & recreation | 2023 |
| JAK Jones Snooker Limited | Arts & recreation | 2024 |
| Jake Dean Property Group Ltd | Real estate | 2024 |
| Jake Suade Limited | Financial services | 2021 |
| Jakmaa Limited | Information & communication | 2018 |
| JAM Basketball Collective CIC | Arts & recreation | 2025 |
| Jamb Construction Building Services Ltd | Construction | 2023 |
| James a. Loffet Limited | Real estate | 1959 |
| James Alexander Woodwork Ltd | Manufacturing | 2023 |
| James Bartlett Ltd | Professional & scientific | 2025 |
| James Critchley Limited | Administrative & support | 2009 |
| James Davidson Associates Ltd | Professional & scientific | 2021 |
| James Harris Advisors Ltd | Professional & scientific | 2025 |
| James Nicol Consulting Limited | Professional & scientific | 2007 |
| James of Montpellier Limited | Wholesale & retail | 2001 |
| James Oliver Smith Holdings Limited | Financial services | 2020 |
| James Street Investments Limited | Real estate | 1988 |
| James Woodward Window Cleaning Ltd | Administrative & support | 2013 |
| Jamie Social Media Limited | Information & communication | 2023 |
| Jamie Williams Design Ltd | Manufacturing | 2012 |
| Jamkat Solutions Limited | Financial services | 2025 |
| Jamm Developments Limited | Construction | 2015 |
| Jane Abson Holdings Limited | Financial services | 2019 |
| Jane Macpherson Yoga Ltd | Health & social care | 2021 |
| Jaox Ltd | Construction | 2017 |
| Jarc BRU Limited | Wholesale & retail | 2020 |
| Jardimzoo Limited | Real estate | 2022 |
| Jarvis Edwards Construction Ltd | Construction | 2026 |
| Jarvix Ltd | Information & communication | 2018 |
| JAS Business Agent Ltd | Real estate | 2023 |
| JAS Global Solutions Limited | Information & communication | 2023 |
| Jaskula Ltd | Real estate | 2026 |
| Jason and Philip Serviced Accommodation Limited | Real estate | 2021 |
| Jason Blanc Limited | Other services | 2026 |
| Jason Cull Racing Ltd | Professional & scientific | 2024 |
| Jasper Asset Management Ltd | Real estate | 2019 |
| Java Joes Ltd | Hospitality | 2023 |
| JAY TEE Phone Repairs Cheltenham Limited | Manufacturing | 2015 |
| Jaycie Limited | Health & social care | 2021 |
| Jaydee Living Limited | Wholesale & retail | 2006 |
| Jayoni Limited | Information & communication | 2014 |
| Jayrosita Limited | Professional & scientific | 2021 |
| JAZ Media Limited | Professional & scientific | 2014 |
| JB Auto Services Ltd | Wholesale & retail | 2011 |
| JB Charles Ltd | Construction | 2016 |
| JB Gentlemen Hairdresser Limited | Other services | 2024 |
| Jbbc Limited | Professional & scientific | 2021 |
| Jbhb Engineering Ltd | Professional & scientific | 2026 |
| Jbhb Holdings Ltd | Real estate | 2019 |
| Jbst Holdings Ltd | Financial services | 2025 |
| Jbst Property Ltd | Real estate | 2025 |
| Jbsy Ltd | Wholesale & retail | 2025 |
| JC Investments and Holdings Ltd | Professional & scientific | 2022 |
| JC Parks & Developments Limited | Real estate | 2017 |
| JC Plastering & Decorating Ltd | Construction | 2024 |
| JC Rose Property Ltd | Real estate | 2025 |
| JCB Events (SW) Limited | Hospitality | 2019 |
| JCF Renovations Ltd | Construction | 2024 |
| JCH Scaffolding Limited | Construction | 2014 |
| JCL Consultancy Limited | Professional & scientific | 2009 |