| Hott Fashion Limited | Manufacturing | 2019 |
| House Coffee and Records Ltd | Wholesale & retail | 2026 |
| House of Dorter Ltd | Real estate | 2026 |
| House of Motion Ltd. | Wholesale & retail | 2024 |
| House of Valuable Vessels --->(Church) | Other services | 2009 |
| House to Home Estate Agents Ltd | Real estate | 2019 |
| House to Home Group Ltd | Other services | 2019 |
| House to Home Lettings Limited | Real estate | 2010 |
| Hoyame Services Limited | Construction | 2025 |
| HP Facilities Ltd | Construction | 2015 |
| HSE Report Assist Ltd | Professional & scientific | 2025 |
| HSS Contractor Limited | Construction | 2023 |
| Hsts Services Ltd | Construction | 2023 |
| Hudash Services Ltd | Construction | 2015 |
| Humble Jacket Ltd | Hospitality | 2025 |
| Hunte Building Specialists Ltd | Construction | 2016 |
| Hybrow Ltd | Construction | 2024 |
| Hyde Construction Ltd | Construction | 2018 |
| I Management Ltd | Households | 2023 |
| I&R Project Ltd | Construction | 2022 |
| I.G. Engineering Limited | Professional & scientific | 2015 |
| I2I by Citipost Facility Management Limited | Administrative & support | 2021 |
| I3 Styles Ltd | Wholesale & retail | 2021 |
| IAM Digital Limited | Administrative & support | 2011 |
| Ianis Logistics Limited | Transport & logistics | 2018 |
| IB Multi Trade Ltd | Construction | 2026 |
| IBI Consultancy Ltd | Real estate | 2024 |
| Ibironke & Famdors Properties Ltd | Real estate | 2024 |
| Ibironke Properties Ltd | Real estate | 2025 |
| Icandoallthingstc Limited | Information & communication | 2018 |
| Ice Auto Services Ltd | Transport & logistics | 2012 |
| Iconic Therapy Ltd | Administrative & support | 2015 |
| Icustodian Limited | Wholesale & retail | 2024 |
| Ideal Candidates Recruitment Limited | Administrative & support | 2017 |
| Idee and Solution Ltd | Information & communication | 2024 |
| Ideoligbo Limited | Professional & scientific | 2025 |
| IDI Facades Ltd | Construction | 2025 |
| Idiarioba Limited | Construction | 2018 |
| IFK Wholesale Trading Ltd | Wholesale & retail | 2025 |
| Igbo Communities London UK Ltd | Other services | 2021 |
| Igors Logistic Ltd | Transport & logistics | 2024 |
| Ikija Care Ltd | Health & social care | 2025 |
| Ildiko Construction Limited | Construction | 2016 |
| Ilirian 2020 Ltd | Construction | 2020 |
| Illawasi Languages & Travel Ltd | Professional & scientific | 2024 |
| Image Catering Limited | Arts & recreation | 2005 |
| Immaculate Concept Limited | Construction | 2022 |
| Imperium Network Limited | Arts & recreation | 2019 |
| Importers Exporters Limited | Wholesale & retail | 2005 |
| Impotech Ltd | Professional & scientific | 2025 |
| IN the AM Ltd | Wholesale & retail | 2021 |
| Inception Support Limited | Information & communication | 2017 |
| Independent Theological Academy Limited | Professional & scientific | 2003 |
| Indigena Wines Limited | Wholesale & retail | 2019 |
| Indigo-I Limited | Professional & scientific | 2024 |
| Indomitable Trading Limited | Construction | 2023 |
| Inehomo Limited | Wholesale & retail | 2020 |
| Ineva Logistics Ltd | Transport & logistics | 2025 |
| Infallible Systems Group Limited | Construction | 2020 |
| Infallible Systems Limited | Construction | 1997 |
| Infinite Sochizin Services Limited | Construction | 2026 |
| Infiniti Homes Ltd | Construction | 2024 |
| Infinity AI Ltd | Administrative & support | 2017 |
| Innovation Partners Consultancy Ltd | Professional & scientific | 2024 |
| Innovation Trading Connection Company Limited | Other services | 2011 |
| Inspired Digi Prints Limited | Information & communication | 2025 |
| INSTALLERS4YOU Ltd | Information & communication | 2021 |
| Instant Digital Limited | Information & communication | 2024 |
| Instinct Painter Ltd | Administrative & support | 2022 |
| Integral Sports Management Limited | Arts & recreation | 2019 |
| Intelcare Ltd | Health & social care | 2020 |
| Intelligent Wealth Planning Ltd | Financial services | 2014 |
| Inter-Steels Limited | Manufacturing | 1987 |
| Intercom Master Ltd | Administrative & support | 2011 |
| Interfirm Allied Services Ltd | Professional & scientific | 2009 |
| Interfirm Homes Ltd | Real estate | 2025 |
| International Consortium for Health Outcomes Measurement Limited | Administrative & support | 2017 |
| International Organisation for Capacity Building London Ltd | Extraterritorial | 2014 |
| International School of Management (ISM) London Limited | Education | 2018 |
| Intersped Logistics (UK) Limited | Transport & logistics | 1982 |
| Interstate 77 Ltd | Wholesale & retail | 2020 |
| Intraflex Talent Ltd | Administrative & support | 2026 |
| Intrust Management Services Ltd | Real estate | 2018 |
| Inve Solutions Limited | Transport & logistics | 2017 |
| IQ Install (UK) Limited | Administrative & support | 2020 |
| Iron Free Limited | Other services | 2024 |
| ISA2 Ltd | Health & social care | 2019 |
| Isac Investment Limited | Real estate | 2024 |
| Isae Properties Limited | Real estate | 2021 |
| Issachar Ventures Ltd | Real estate | 2015 |
| IT IS Time Ltd | Health & social care | 2022 |
| IT Projects Consulting Ltd | Professional & scientific | 2016 |
| Itech Solutions Limited | Information & communication | 2025 |
| IVO Ltd | Construction | 2013 |
| IVY Cars 4U Ltd | Wholesale & retail | 2023 |
| IW Estate Planning Ltd | Financial services | 2013 |
| Iwisuk Ltd | Real estate | 2021 |
| J & J Management (London) Ltd | Real estate | 2025 |
| J & P Housing Ltd | Real estate | 2025 |
| J Brown Properties LLP | | 2008 |