| JRC Property Holdings Ltd | Real estate | 2011 |
| JRF Solutions Limited | Information & communication | 2009 |
| JRL Driver Hire Limited | Transport & logistics | 2025 |
| JRN Properties Limited | Construction | 2011 |
| JRS Property Ltd | Households | 2025 |
| Jrti Consulting Ltd | Professional & scientific | 2023 |
| JS & JS Developments Ltd | Real estate | 2020 |
| JS (Cheltenham) Ltd | Real estate | 2024 |
| JS and OS Holdings Limited | Financial services | 2020 |
| JS Decorating Ltd | Construction | 2014 |
| JS Green Ltd | Health & social care | 2012 |
| JSC7 Engineering Ltd | Professional & scientific | 2022 |
| JSC7 Talent Ltd | Administrative & support | 2025 |
| Jslb & Hollingshead Ltd | Wholesale & retail | 2022 |
| JSN Carpentry Ltd | Manufacturing | 2021 |
| JSP Environmental Limited | Extraterritorial | 1984 |
| JSP Limited | Manufacturing | 1964 |
| JST Coaching Ltd | Education | 2018 |
| JSW Build Ltd | Real estate | 2024 |
| JSW Retail Limited | Wholesale & retail | 2025 |
| JTK Pubs Limited | Hospitality | 2026 |
| Jubilee Seeds & Turf Limited | Administrative & support | 2016 |
| Judith Afro and Beauty Store Ltd | Wholesale & retail | 2024 |
| Judith Ethnic Food Store Ltd | Wholesale & retail | 2021 |
| Judith Kitchen Takeaway Limited | Hospitality | 2026 |
| Julia & K Limited | Professional & scientific | 2025 |
| Julian Day Farrier Limited | Agriculture & fishing | 2008 |
| Juliana Greenhouses Ltd | Manufacturing | 1985 |
| Julians Hair Salons Limited | Other services | 2011 |
| Julie Sullivan (Chipping Campden) Limited | Other services | 2022 |
| Juliet Davenport Consulting Ltd | Professional & scientific | 2018 |
| Juliette Armand Limited | Health & social care | 2019 |
| Juliettemoxhamwellbeing Ltd | Health & social care | 2026 |
| Jumbleberries@ Ltd | Construction | 2018 |
| Jumpcloud UK Limited | Administrative & support | 2022 |
| Jumping Giraffe Ltd | Information & communication | 2012 |
| JUN Valley Trading Limited | Wholesale & retail | 2023 |
| Junction 9 Holdings Limited | Real estate | 2019 |
| Junction 9 NO. 1 Limited | Real estate | 2019 |
| Junction 9 NO. 2 Limited | Real estate | 2019 |
| Junction 9 NO. 3 Limited | Real estate | 2020 |
| Junkosha UK Limited | Professional & scientific | 2017 |
| Jupiter Stone Properties Ltd | Households | 2025 |
| Just BE YOU Bridal Ltd | Wholesale & retail | 2023 |
| Just Camps Consultancy Limited | Professional & scientific | 2019 |
| Just Camps Ltd | Health & social care | 2017 |
| Just Diagnostics Limited | Wholesale & retail | 2018 |
| Just Go Holidays Limited | Administrative & support | 2002 |
| Just Go Transport Limited | Transport & logistics | 2009 |
| Just Ranke Ltd | Wholesale & retail | 2025 |
| Just ROW Gloucestershire Rowing Club Ltd | Education | 2025 |
| Just Wooden Toys Limited | Wholesale & retail | 2017 |
| Just Yachts Solutions Ltd | Education | 2023 |
| Justalittlebit.Co.Uk Ltd | Wholesale & retail | 2014 |
| Justchestphysio Limited | Professional & scientific | 2013 |
| Justpmit Limited | Information & communication | 1997 |
| Juvenate Media Ltd | Information & communication | 2013 |
| JV Consultancy Group Limited | Professional & scientific | 2020 |
| Jvat Developments Limited | Construction | 2020 |
| JWK Roofing Limited | Construction | 2023 |
| Jworx Classic Ltd | Wholesale & retail | 2017 |
| JWR Carpentry & Joinery Ltd | Manufacturing | 2021 |
| JY Property Cheltenham Limited | Construction | 2025 |
| JY Restaurants Limited | Hospitality | 2024 |
| JYS Restaurants Limited | Hospitality | 2025 |
| K & P Consulting Limited | Administrative & support | 2004 |
| K & R Management Services Limited | Real estate | 2014 |
| K & R Vehicle Solutions Limited | Manufacturing | 2009 |
| K C Stevens Food Limited | Hospitality | 2024 |
| K Head Developments Limited | Construction | 2011 |
| K J Harwood Limited | Professional & scientific | 2011 |
| K Maids Ltd | Administrative & support | 2021 |
| K Mitchell Services Ltd | Information & communication | 2025 |
| K N K Cheltenham Ltd | Financial services | 2014 |
| K N Mitchell Consulting Limited | Transport & logistics | 2012 |
| K&N IMP and EXP Ltd | Wholesale & retail | 2025 |
| K&N Stables Ltd | Agriculture & fishing | 2020 |
| K&Y Stroud Ltd | Wholesale & retail | 2025 |
| K-Tech Networks Limited | Information & communication | 2025 |
| K-Ten Consulting Ltd | Professional & scientific | 2023 |
| K-Works Studio Ltd | Professional & scientific | 2023 |
| K.Murray & Company Limited | Construction | 1963 |
| K.P.S.B. Limited | Information & communication | 1997 |
| K.R. Electrical/Products Limited | Construction | 2001 |
| K2 Care (South West) Ltd | Health & social care | 2016 |
| K2 Performance Limited | Professional & scientific | 2025 |
| K2 Performance Systems (UK) Limited | Professional & scientific | 2006 |
| K2 Performance Systems International Limited | Professional & scientific | 2013 |
| Ka-Kr Logistic Ltd | Transport & logistics | 2026 |
| Kaaren Buchanan Limited | Manufacturing | 2019 |
| Kabelo and Lebo Trademark Limited | Health & social care | 2013 |
| Kactus Technologies Limited | Information & communication | 2022 |
| Kaffi Ltd | Information & communication | 2026 |
| Kafue Investment Consultants Limited | Professional & scientific | 2009 |
| Kagun Limited | Real estate | 2019 |
| Kajol & Nancy Limited | Real estate | 2005 |
| Kalako Ltd | Administrative & support | 2017 |
| Kaljam Ltd | Real estate | 2019 |
| Kaloo Medical Ltd | Health & social care | 2020 |
| KAM Performing Arts Academy CIC | Arts & recreation | 2025 |