| Jeffrey Parker and Company Limited | Professional & scientific | 2011 |
| Jeffries Autobarn Ltd | Wholesale & retail | 2026 |
| Jega Enterprises Ltd | Other services | 2025 |
| JEK Construction Ltd | Construction | 2014 |
| Jelignite Ltd | Information & communication | 2017 |
| Jelly Entertainment Ltd | Information & communication | 2020 |
| Jellyfish Norfolk CIC | Health & social care | 2026 |
| Jemco Limited | Other services | 2015 |
| Jempress Limited | Financial services | 2008 |
| Jems Environmental Limited | Manufacturing | 2013 |
| Jemygetaways Ltd | Hospitality | 2023 |
| JEN Sands & Co. Ltd | Professional & scientific | 2026 |
| Jen's Kitchen Limited | Professional & scientific | 2019 |
| JEN2 Limited | Professional & scientific | 2023 |
| Jenkinson Properties Limited | Construction | 1989 |
| Jenmad Ltd | Health & social care | 2013 |
| Jenni Doggett Limited | Professional & scientific | 2012 |
| Jennifer Grace Music and Vocal Academy Limited | Education | 2018 |
| Jennifer Orode Limited | Other services | 2021 |
| Jennings Marketing Limited | Wholesale & retail | 2025 |
| Jennison Accounting Ltd | Professional & scientific | 2022 |
| Jenny Broom Publishing Ltd | Information & communication | 2018 |
| Jenson James Property Investments Ltd | Real estate | 2021 |
| Jensten Insurance Brokers (East) Limited | Financial services | 2010 |
| Jenton Aero Ltd | Manufacturing | 2017 |
| Jepps Lane Management Limited | Households | 2004 |
| Jeremy Clark Accountants Ltd | Professional & scientific | 2009 |
| Jerf Limited | Administrative & support | 2019 |
| Jermedia Ltd | Professional & scientific | 2023 |
| Jermyn & Co Accountants Limited | Professional & scientific | 2022 |
| Jermyn Holdings Limited | Financial services | 2025 |
| Jermyn Taylor Limited | Professional & scientific | 2017 |
| Jerni | Financial services | 2026 |
| Jerry March Funeral Services Limited | Other services | 2024 |
| Jervis Commercial Ltd | Real estate | 2022 |
| Jervis Consulting Limited | Professional & scientific | 2019 |
| Jervis Estates Limited | Real estate | 2016 |
| Jesfry Ltd | Other services | 2017 |
| Jess Consultancy Ltd | Health & social care | 2014 |
| Jesse Onslow Limited | Information & communication | 2022 |
| Jessfield Consulting Ltd | Professional & scientific | 2016 |
| Jessie Leakily Ltd | Information & communication | 2017 |
| Jesus Christ Source of Life Church Ltd | Extraterritorial | 2022 |
| JET Social Ltd | Information & communication | 2012 |
| JET Wings Travels Ltd | Transport & logistics | 2023 |
| Jetani Brothers UK Ltd | Administrative & support | 2014 |
| Jetro Ltd | Wholesale & retail | 2023 |
| Jettco Drywall Ltd | Construction | 2010 |
| Jewel ARK Ltd | Wholesale & retail | 2010 |
| Jewell Group Limited | Construction | 2025 |
| Jewellbox.Uk Limited | Wholesale & retail | 2020 |
| JF Financial Associates Ltd | Professional & scientific | 2014 |
| JF KAY Consultancy Ltd | Administrative & support | 2023 |
| JF KAY Ltd | Administrative & support | 2018 |
| JF Kennedy Consultants Limited | Professional & scientific | 2014 |
| JF Property Lettings Limited | Real estate | 2010 |
| JFA Plumbing & Bathrooms Limited | Construction | 2025 |
| JFR Components Limited | Wholesale & retail | 2015 |
| JFT Services Limited | Professional & scientific | 2002 |
| JFW Wealth Management Ltd | Financial services | 2024 |
| Jfwade Limited | Professional & scientific | 2023 |
| JG Renewables Ltd | Manufacturing | 2018 |
| JG Triple M Limited | Wholesale & retail | 2019 |
| JGM UK Services Limited | Administrative & support | 2021 |
| JGS Hotels Ltd | Hospitality | 2022 |
| JH Bagshaw Metal Limited | Manufacturing | 2011 |
| JH Nature Ltd | Health & social care | 2014 |
| JH Photography and Film Ltd | Information & communication | 2024 |
| JH Plumbing and Heating (Norfolk) Limited | Construction | 2008 |
| JH Services Ltd | Construction | 2023 |
| JH Trade Ltd | Wholesale & retail | 2023 |
| Jh&R Properties Ltd | Real estate | 2022 |
| Jheet Limited | Other services | 2023 |
| Jhony & ALY Drive Limited | Transport & logistics | 2013 |
| JHR Car Sales Ltd | Wholesale & retail | 2024 |
| JHS Electrical Limited | Construction | 2017 |
| JHW Azoth Capital Ltd | Professional & scientific | 2025 |
| JHW Azoth Ltd | Professional & scientific | 2025 |
| JHW Business Services Ltd | Professional & scientific | 2019 |
| JHW Consulting (Norfolk) Ltd | Professional & scientific | 2026 |
| JHZ Sackey Ltd | Health & social care | 2025 |
| Jiachen Ltd | Hospitality | 2025 |
| JIC NRP Capital Limited | Professional & scientific | 2007 |
| Jigsaw Accounting and Tax Ltd | Professional & scientific | 2019 |
| Jimmy COX Hairdressing Ltd | Other services | 2018 |
| Jimmy's Mazda RX7 Specialists Limited | Wholesale & retail | 2001 |
| Jingo Ventures Limited | Agriculture & fishing | 2020 |
| Jinopalakalam Ltd | Health & social care | 2025 |
| JIR Consulting Ltd | Professional & scientific | 2025 |
| Jiva Consulting Ltd | Professional & scientific | 2024 |
| Jive Kitchen Ltd | Hospitality | 2019 |
| JIWAN83 Ltd | Real estate | 2023 |
| JJ Bilton Ltd | Hospitality | 2023 |
| JJ Builders Norfolk Limited | Construction | 2023 |
| JJ Corp Properties Ltd | Real estate | 2022 |
| JJ Investment Properties Ltd | Real estate | 2019 |
| JJ Property Maintenance (Norfolk) Ltd | Administrative & support | 2024 |
| JJ Steel Consultancy Ltd | Construction | 2024 |
| JJ Subs Ltd | Hospitality | 2018 |
| JJ Taylor Interiors Ltd | Professional & scientific | 2024 |