| Isle of Culture CIC | Education | 2026 |
| ISO Harmony Health Ltd | Wholesale & retail | 2025 |
| It's a Fit Future Ltd | Wholesale & retail | 2023 |
| Italy's Independent International Film Festival Limited | Information & communication | 2013 |
| ITT Nutrition Ltd | Wholesale & retail | 2026 |
| Ivory Healthcare Services Ltd | Health & social care | 2023 |
| Izlo Design Ltd | Professional & scientific | 2025 |
| Izzy Buck Ltd | Administrative & support | 2025 |
| J & C Ellis Limited | Professional & scientific | 2017 |
| J & E Palace Ltd | Hospitality | 2019 |
| J & J Colleary (Building Services) Ltd | Real estate | 2015 |
| J & J Colleary Limited | Construction | 2007 |
| J & P Garden Products Ltd | Manufacturing | 2021 |
| J Mathews Services Ltd | Construction | 2020 |
| J R C Electrical Contractors Limited | Construction | 2007 |
| J RYE Construction & Kent Home Extensions Ltd | Construction | 2025 |
| J S a Edwards Associates Ltd | Arts & recreation | 2014 |
| J W Training Limited | Education | 2015 |
| J Y Margate Ltd | Real estate | 2022 |
| J&K Abodes Ltd | Construction | 2021 |
| J&K Services (Group) Ltd | Administrative & support | 2011 |
| J&S Kent Ltd | Construction | 2026 |
| J. Ballantyne Limited | Real estate | 2022 |
| J.A.N Developments Kent Ltd | Administrative & support | 2017 |
| J.A.N Holdings Kent Ltd | Real estate | 2019 |
| J.A.N Residential Ltd | Real estate | 2020 |
| J.E.B Electricals (Kent) Ltd | Construction | 2018 |
| Jaab Homes Ltd | Real estate | 2019 |
| Jaben's Castle Ltd | Extraterritorial | 2023 |
| Jacel Limited | Real estate | 2015 |
| Jack Day Hair & Beauty Limited | Other services | 2023 |
| Jack House Limited | Manufacturing | 2021 |
| Jackson Landscapes Ltd | Administrative & support | 2022 |
| JAG Roofing Services Limited | Construction | 2021 |
| James Driver Hire & Consulting Ltd | Transport & logistics | 2020 |
| James Fleming Associates Ltd. | Professional & scientific | 2014 |
| James Power Services Limited | Construction | 2023 |
| James Riley Solutions Ltd | Professional & scientific | 2026 |
| Jamface Ltd. | Manufacturing | 2015 |
| Jamieson Avenue Development's & Acquisitions Ltd | Real estate | 2019 |
| Japanthai Catering Limited | Hospitality | 2017 |
| Jardins Close Ramsgate Management Company Limited | Households | 2008 |
| Jason Glanville Ltd | Construction | 2013 |
| JAW Ceramics CIC | Arts & recreation | 2024 |
| JAX Dyer Estates Limited | Real estate | 2024 |
| Jazs House Ltd | Arts & recreation | 2025 |
| Jazs Jaggers Ltd | Arts & recreation | 2025 |
| JB Auto Sales South East Ltd | Wholesale & retail | 2024 |
| JB Logistics Ltd | Transport & logistics | 2025 |
| JBS Carpentry Ltd | Construction | 2022 |
| JCW Partners Limited | Real estate | 2023 |
| JD Davis Property Ltd | Real estate | 2020 |
| JD Margate Express Ltd | Wholesale & retail | 2021 |
| JEL & Sons Ltd | Construction | 2025 |
| Jenions Ltd | Wholesale & retail | 2023 |
| JET SKI World Ltd | Arts & recreation | 2019 |
| Jetbordz Ltd | Wholesale & retail | 2024 |
| Jetty Bistro Ltd | Hospitality | 2025 |
| Jetty Holdings Ltd | Financial services | 2025 |
| Jetty Seafood Broadstairs Ltd | Hospitality | 2020 |
| JFK IT Solutions Ltd | Information & communication | 2016 |
| JFK Property Solutions Limited | Real estate | 2019 |
| JG Projects Ltd | Professional & scientific | 2022 |
| JH Sealants Ltd | Manufacturing | 2024 |
| Jim's Lets Limited | Hospitality | 2016 |
| Jimmy and INI Ltd | Other services | 2023 |
| Jive and Blues 2 Health Limited | Health & social care | 2015 |
| JJ Brothers Private Limited | Health & social care | 2022 |
| JJ Properties Kent Ltd | Real estate | 2021 |
| JJL Offshore Services Ltd | Manufacturing | 2023 |
| JJS Brickwork Ltd | Construction | 2018 |
| Jjsoffshoreservices Limited | Construction | 2025 |
| Jkjn Property Limited | Real estate | 2020 |
| JL Farm Enterprises Ltd | Agriculture & fishing | 2018 |
| Jlbm Design Ltd | Professional & scientific | 2026 |
| JLC Investments Kent Ltd | Financial services | 2022 |
| JM Website Design Limited | Information & communication | 2023 |
| JMB Property Group Limited | Real estate | 2024 |
| JN Investment Properties Ltd | Real estate | 2023 |
| JN Sholden Store Ltd | Wholesale & retail | 2023 |
| JNW Electrical Kent Ltd | Construction | 2019 |
| Jodie & Co. Ltd | Arts & recreation | 2026 |
| Joefix Limited | Health & social care | 2023 |
| Joel Express Ltd | Wholesale & retail | 2026 |
| Joel Knight Photography Ltd | Professional & scientific | 2019 |
| John Ferguson Spares Limited | Other services | 2002 |
| John SIN Limited | Construction | 2019 |
| Johnson Plumbing & Heating Ltd | Construction | 2020 |
| Johnston Marketing Limited | Professional & scientific | 2020 |
| Jolly Boys Margate Limited | Hospitality | 2025 |
| Jolly Rambler Limited | Professional & scientific | 2013 |
| JON DIX Music Ltd | Information & communication | 2026 |
| JON Watkins Consulting Services (Jwcs) Ltd | Information & communication | 2019 |
| Jonathan Bentman Limited | Information & communication | 2011 |
| Jordan Mary Photography Limited | Professional & scientific | 2019 |
| Joseph Hodges Entertainment Limited | Arts & recreation | 2020 |
| Joshua and Jerome Properties Ltd | Real estate | 2022 |
| Joyavista Ltd | Information & communication | 2026 |
| JP Schmitt T/A Schmitt London Limited | Manufacturing | 2024 |
| JPK Car Parts Limited | Wholesale & retail | 2018 |