| Homeline Property Services Ltd | Construction | 2012 |
| Horizon Management & Consultancy Limited | Professional & scientific | 2026 |
| Hotsmart Auot Ltd | Wholesale & retail | 2025 |
| House of ADA Ltd. | Hospitality | 2018 |
| House of Gilgal Ltd | Wholesale & retail | 2025 |
| Housemakeruk Limited | Real estate | 2025 |
| Hugo’S Mobile Tyres Ltd | Wholesale & retail | 2025 |
| Hulley-Vale Limited | Administrative & support | 2021 |
| Humblet Services Limited | Manufacturing | 2022 |
| Husnain Network Ltd | Wholesale & retail | 2025 |
| Hxkng Ltd | Wholesale & retail | 2021 |
| Hydeal UK Limited | Other services | 2016 |
| I & S Integrated Services Ltd | Professional & scientific | 2012 |
| Iason Trans Ltd | Transport & logistics | 2015 |
| IB Serv Ltd | Construction | 2014 |
| IB2 Logistics Ltd | Transport & logistics | 2022 |
| Icml Transport Limited | Transport & logistics | 2017 |
| Id-Vision Services Limited | Health & social care | 2020 |
| Ideal 4 Limited | Construction | 2015 |
| IEG Services Limited | Administrative & support | 2026 |
| IFE Consultancy Ltd | Administrative & support | 2016 |
| IFE Properties Ltd | Real estate | 2018 |
| IG Fixing Services Limited | Construction | 2015 |
| Iiee Global Engineers Ltd | Administrative & support | 2012 |
| Ilio 7 Ltd | Transport & logistics | 2018 |
| Imedok Ltd | Information & communication | 2012 |
| Impact Catering Ltd | Hospitality | 2019 |
| IN Doors Limited | Manufacturing | 2004 |
| INB Contractor Ltd | Construction | 2012 |
| Inclusive Care Services Limited | Health & social care | 2015 |
| Incyyte Limited | Information & communication | 2011 |
| Index London Limited | Wholesale & retail | 2022 |
| Indians in Thurrock Ltd | Other services | 2023 |
| Indulgent Cakes Limited | Manufacturing | 2024 |
| Ineawo Properties Limited | Real estate | 2025 |
| Infinito Property Limited | Real estate | 2025 |
| Infinity TEL Limited | Information & communication | 2025 |
| Inngate Limited | Wholesale & retail | 2006 |
| Innomaco Services (UK) Limited | Administrative & support | 2014 |
| Innovators Commerce Ltd | Wholesale & retail | 2021 |
| Integrated Kare Solutions Limited | Health & social care | 2018 |
| Interim Link Limited | Information & communication | 2014 |
| Interio Limited | Construction | 2018 |
| Intershore Engineering Ltd | Professional & scientific | 2012 |
| Intertrade Drylining and Interiors Limited | Construction | 2026 |
| Investment BEE Ltd | Real estate | 2021 |
| ION Popa Ltd | Construction | 2017 |
| Ionica Services Ltd | Construction | 2016 |
| Ionshop Ltd | Wholesale & retail | 2025 |
| IQB Properties Limited | Real estate | 2025 |
| Iqra Care Ltd | Health & social care | 2025 |
| Iron Quality Services Ltd | Construction | 2025 |
| ISP Installation Ltd | Construction | 2022 |
| Istanbul Barber South Ockendon Limited | Other services | 2019 |
| IT Vision Consultancy Services Limited | Information & communication | 2011 |
| Italian Cookshop Ltd | Wholesale & retail | 2023 |
| IU Properties Limited | Real estate | 2023 |
| Ivan Cleaning and Maintenance Ltd | Administrative & support | 2013 |
| IZ Szabo Ltd | Administrative & support | 2015 |
| Izhaan Distribution UK Limited | Information & communication | 2024 |
| J & VIC Construction Ltd | Construction | 2025 |
| J Caine Ltd | Real estate | 2019 |
| J Nichols Limited | Professional & scientific | 2025 |
| JA Akinbode & Sons Limited | Transport & logistics | 2012 |
| Jadestar Restaurant Limited | Hospitality | 2012 |
| Jags Essex Services Ltd | Information & communication | 2022 |
| James N.M Care Solutions Ltd | Health & social care | 2024 |
| James Plumbing and Heating Services Limited | Construction | 2019 |
| Janet Fayemi and Associates Ltd | Professional & scientific | 2025 |
| Janetdistribution Limited | Wholesale & retail | 2025 |
| Jasmal Ltd | Public administration | 2019 |
| Jaura Ltd | Construction | 2022 |
| Javestra Solutions Ltd | Manufacturing | 2021 |
| Jayhk Property Ltd | Real estate | 2023 |
| Jaytee Consultants Ltd | Professional & scientific | 2013 |
| Jbrain Software Ltd | Information & communication | 2009 |
| JBULLETS3 Limited | Construction | 2018 |
| JC and Sons Electrical Ltd | Construction | 2020 |
| JC Rising Ltd | Real estate | 2018 |
| Jcla Solutions Ltd | Professional & scientific | 2026 |
| JCS Poster Site Construction Ltd | Construction | 2013 |
| JCS PSC Holdings Limited | Financial services | 2019 |
| JCT Contractor Services Ltd | Construction | 2023 |
| Jctt Properties Limited | Real estate | 2017 |
| JCZ Systems Ltd | Construction | 2023 |
| JD & YH Holdings Ltd | Construction | 2022 |
| JD Smart Electrical Ltd | Construction | 2019 |
| JDO 10 Ltd | Transport & logistics | 2025 |
| JDS Security Services Ltd | Administrative & support | 2025 |
| Jeruni Ltd | Real estate | 2025 |
| Jessica Ikpeme Ltd | Health & social care | 2024 |
| Jessika Trans Ltd | Transport & logistics | 2018 |
| Jetoni Transport Ltd | Transport & logistics | 2016 |
| Jewels Independent Prescribing Service Ltd | Wholesale & retail | 2024 |
| Jhemm Graphics Limited | Wholesale & retail | 2022 |
| Jitaru Construction Ltd | Construction | 2022 |
| JJ Food City Ltd | Wholesale & retail | 2025 |
| JJF Maintenance Limited | Administrative & support | 2015 |
| JKL Builds Limited | Construction | 2025 |
| JKV Construction Ltd | Construction | 2025 |