| Johal Concrete Ltd | Construction | 2018 |
| Johal Construction Services Ltd | Construction | 2023 |
| Johal Gold Star Ltd | Transport & logistics | 2025 |
| Johal Property Maintenance (UK) Ltd | Real estate | 2023 |
| Johal Services LLP | | 2019 |
| John & Sons Solutions Limited | Manufacturing | 2025 |
| John Arlington Homes Limited | Construction | 2022 |
| John Best Kitchens Limited | Hospitality | 2026 |
| John Crane Group Limited | Professional & scientific | 2004 |
| John D R Cole Ltd | Professional & scientific | 2025 |
| John Garry Spraggon Ltd | Construction | 2010 |
| Johnro Ltd | Wholesale & retail | 2016 |
| Johnson KD Limited | Wholesale & retail | 2020 |
| Johnson's Tree Surgery Ltd | Administrative & support | 2020 |
| Joik Health Limited | Professional & scientific | 2020 |
| Joint Posture Ltd | Health & social care | 2019 |
| Jojo and MAX Limited | Other services | 2014 |
| Jojosperiperi Ltd | Wholesale & retail | 2021 |
| JOL London Ltd | Wholesale & retail | 2021 |
| Jolly Jotters Ltd | Wholesale & retail | 2021 |
| JON BOY Services (Slough) Limited | Other services | 2013 |
| JON Staple Ltd | Other services | 2019 |
| Jona Singh Ltd | Construction | 2018 |
| Jonal Care Limited | Health & social care | 2021 |
| Jonathan Curtis Limited | Professional & scientific | 2016 |
| Jonida Ltd | Real estate | 2017 |
| Jonson Transport Solutions Ltd | Transport & logistics | 2013 |
| Jordanzion Personnel Ltd | Health & social care | 2015 |
| Joroma (Burnham) Limited | Administrative & support | 2018 |
| Jorra Ltd | Arts & recreation | 2020 |
| Josa Collections Limited | Administrative & support | 2023 |
| Josephine Buchan Productions Limited | Arts & recreation | 2006 |
| Josh Harwood Construction Ltd | Construction | 2022 |
| Jotopia Ltd | Health & social care | 2019 |
| Joyes Taverns Ltd | Hospitality | 2026 |
| Joymac Care Ltd | Health & social care | 2016 |
| Joyrise Recruitment Solutions Limited | Health & social care | 2017 |
| JP Construction Consultants Ltd | Real estate | 2024 |
| JP Real Estate Investors Ltd | Real estate | 2024 |
| JPA Europe Limited | Professional & scientific | 2013 |
| Jpccen Global Ltd | Wholesale & retail | 2026 |
| Jphr Holdings Ltd | Financial services | 2025 |
| JPJ & Sons Ltd | Wholesale & retail | 2020 |
| Jplees Pharma Services Ltd | Professional & scientific | 2016 |
| JPM Hill Limited | Information & communication | 2024 |
| JPN Enterprises Limited | Wholesale & retail | 2019 |
| JPN Services Limited | Wholesale & retail | 2023 |
| JPS Building Services Limited | Construction | 2011 |
| JPS Horizon Ltd | Information & communication | 2025 |
| JPW (Maidenhead) Ltd | Construction | 2019 |
| JQB Services Limited | Information & communication | 2018 |
| JR Intelligence Ltd | Professional & scientific | 2008 |
| JR Joaquin Backyard Garage Company Limited | Wholesale & retail | 2024 |
| JRD Metal Works Limited | Manufacturing | 2025 |
| Jrjl Limited | Health & social care | 2019 |
| JRL Construction Ltd | Construction | 2023 |
| Jrny Property Limited | Real estate | 2025 |
| JRS Management Services Ltd | Hospitality | 2019 |
| Jrts Tech Limited | Information & communication | 2025 |
| JRV Solutions Ltd | Information & communication | 2012 |
| JS & BK Riar Transport Ltd | Transport & logistics | 2021 |
| JS Construction Associates Ltd | Real estate | 2025 |
| JS Crown Roofing Ltd | Construction | 2026 |
| JS Dhillon Limited | Health & social care | 2015 |
| JS Glazing Ltd | Construction | 2014 |
| JS Haulage Services Limited | Transport & logistics | 2026 |
| JS Kamboj Ltd | Transport & logistics | 2020 |
| JS Project SD Ltd | Other services | 2022 |
| JS Property Maintenance Services Limited | Other services | 2026 |
| JS Sandhu Transport Limited | Transport & logistics | 2015 |
| JS Tech Ltd | Wholesale & retail | 2022 |
| JS UK Service Limited | Transport & logistics | 2017 |
| JSA Roofing Service Ltd | Construction | 2022 |
| Jsandhu Properties Limited | Real estate | 2022 |
| JSD Dental Holdings Limited | Professional & scientific | 2012 |
| JSD Logistics London Limited | Transport & logistics | 2026 |
| Jseo Limited | Wholesale & retail | 2025 |
| JSG Courier Services Limited | Transport & logistics | 2015 |
| JSG Haulier Ltd | Transport & logistics | 2013 |
| JSG Lettings Ltd | Real estate | 2020 |
| Jsh-R Ltd | Hospitality | 2025 |
| Jshloosemoreuk Ltd | Hospitality | 2025 |
| JSJ Couriers Limited | Transport & logistics | 2020 |
| JSJ Housing Limited | Real estate | 2024 |
| JSK UK Investments Ltd | Real estate | 2024 |
| JSR Couriers Ltd | Transport & logistics | 2021 |
| Jsrc Ltd | Wholesale & retail | 2025 |
| Jsrm Construction Ltd | Construction | 2019 |
| JSS Haulage Ltd | Transport & logistics | 2016 |
| JSS Over Limited | Construction | 2025 |
| Jssp Staffing Services Ltd | Construction | 2021 |
| Jsstudio-Ldn Ltd | Professional & scientific | 2026 |
| JSV Investments Ltd | Financial services | 2021 |
| JT Bloom Property UK Ltd | Real estate | 2026 |
| JT Transport and Freight Ltd | Transport & logistics | 2025 |
| JTD Secure Ltd | Administrative & support | 2023 |
| JTG Electrical Services Limited | Construction | 2025 |
| JTL Global Ventures Limited | Administrative & support | 2008 |
| JTP Skip Hire Limited | Transport & logistics | 2024 |
| JTR Security Ltd | Administrative & support | 2013 |