| HP Plant Hire Ltd | Administrative & support | 2019 |
| HQA Repairs Ltd | Wholesale & retail | 2025 |
| Hrwise Consulting Ltd | Administrative & support | 2026 |
| Human Touch Recruitment Ltd | Administrative & support | 2022 |
| Hypnoq Limited | Wholesale & retail | 2025 |
| Hythe Local Ltd | Wholesale & retail | 2021 |
| I M Electrical Solutions Limited | Construction | 2020 |
| I M Quality Services Limited | Construction | 2018 |
| I&B Cover Ltd | Construction | 2023 |
| I2I by Citipost Limited | Transport & logistics | 2012 |
| Idabel Ltd | Other services | 2024 |
| Ideal Home for YOU Ltd | Real estate | 2022 |
| Ideventures Ltd | Wholesale & retail | 2018 |
| Imperial Mortgages Ltd | Financial services | 2006 |
| Incodesoft Limited | Information & communication | 2026 |
| Infinitive Edge Limited | Information & communication | 2025 |
| Infinity Estates & Retreats Limited | Construction | 2023 |
| Inkaba C.I.C. | Health & social care | 2026 |
| Innonwatu Ltd | Transport & logistics | 2024 |
| Innovade Limited | Manufacturing | 2020 |
| Inovserve Ltd | Information & communication | 2014 |
| Inspired Community Group CIC | Administrative & support | 2020 |
| Inspiring Lives Supported Homes C.I.C. | Health & social care | 2019 |
| Install AV Limited | Manufacturing | 2003 |
| Install-Design Limited | Construction | 2020 |
| Integrada Ltd | Information & communication | 2022 |
| Integrity Accounting Ltd | Professional & scientific | 2016 |
| Inter Infinity Ltd | Construction | 2022 |
| Interior Partnerships Limited | Construction | 2008 |
| Interm Ltd | Construction | 2015 |
| Intl Tax & UX Limited | Information & communication | 2026 |
| IQ Distribution Limited | Extraterritorial | 2024 |
| IQ Energy (Services) Ltd | Wholesale & retail | 2013 |
| IQ Property Relocations Ltd | Extraterritorial | 2024 |
| Iron Rose Ltd | Real estate | 2022 |
| ITA Interiors Limited | Construction | 2021 |
| Itma Care Ltd | Health & social care | 2023 |
| Iukgo Ltd | Wholesale & retail | 2023 |
| IX3 Ltd | Wholesale & retail | 2025 |
| Iyore Investments Ltd | Administrative & support | 2018 |
| J M Fusion Limited | Wholesale & retail | 2016 |
| J Ultimate Ltd | Construction | 2017 |
| J&A Sandhu Ltd | Construction | 2023 |
| J.Innes.Bathrooms Ltd | Construction | 2025 |
| J2 Flooring Group Ltd | Construction | 2022 |
| Jade Childcare Ltd | Education | 2024 |
| Jadhav Group Limited | Information & communication | 2024 |
| Jaish Vision Ltd | Health & social care | 2025 |
| Jamm Trade Ltd | Hospitality | 2023 |
| JAS 4 Building Limited | Construction | 2021 |
| Jatlan Properties Ltd | Real estate | 2020 |
| JD Beauty Bar Ltd | Other services | 2025 |
| Jeffery James Ltd | Arts & recreation | 2022 |
| Jehovah Gimollah Limited | Other services | 2014 |
| Jenny Remmy Limited | Health & social care | 2022 |
| Jesada Panich Limited | Wholesale & retail | 2014 |
| JF Feehan Limited | Agriculture & fishing | 2025 |
| Jheeta Real Estate Ltd | Real estate | 2022 |
| JHK Construction Limited | Construction | 2005 |
| Jiaozi Ltd | Hospitality | 2024 |
| JJO Limited | Health & social care | 2023 |
| Jofel Limited | Health & social care | 2017 |
| Johnson & Daniel Lettings & Maintenance Ltd | Real estate | 2024 |
| Jones Haulage Ltd | Transport & logistics | 2020 |
| Jonnel's Limited | Real estate | 2014 |
| Joshday Day Limited | Information & communication | 2018 |
| Joshiwashi Ltd | Wholesale & retail | 2025 |
| Jossylad Ltd | Administrative & support | 2024 |
| JPL Global Ltd | Wholesale & retail | 2024 |
| JT Industries Ltd | Wholesale & retail | 2023 |
| JT Pro Consultancy Ltd | Financial services | 2015 |
| June Food&Drink Ltd | Hospitality | 2022 |
| Junta Group Limited | Administrative & support | 2024 |
| Justconnect Consultancy Limited | Health & social care | 2021 |
| Justfabums Events Ltd | Hospitality | 2026 |
| K Highway Windows & Doors Ltd | Construction | 2021 |
| K Jandu Services Limited | Transport & logistics | 2022 |
| K.Sharma Consulting Limited | Professional & scientific | 2024 |
| KAF Enterprises Limited | Real estate | 2024 |
| KAI Commercials Limited | Transport & logistics | 2009 |
| Kalala Express Limited | Real estate | 2005 |
| Kamraj Properties Ltd | Real estate | 2023 |
| Karaire Limited | Wholesale & retail | 2024 |
| Karelove Limited | Health & social care | 2017 |
| Kasso Properties Ltd | Real estate | 2026 |
| KD Electrical (London) Ltd | Construction | 2019 |
| Kedey Ltd | Transport & logistics | 2018 |
| Kegaro Ltd | Information & communication | 2025 |
| Kelvin Nwatu Ltd | Transport & logistics | 2026 |
| Kent Asset Management Limited | Real estate | 2017 |
| Kent Crash Repairs Limited | Wholesale & retail | 2018 |
| Kent Developers Solutions Ltd | Construction | 2024 |
| Kent Print & Sign Ltd | Manufacturing | 2017 |
| Kenton (UK) Ltd | Extraterritorial | 2014 |
| Kestas&Co(London) Ltd | Construction | 2016 |
| KG Editing Ltd | Information & communication | 2017 |
| Khefem Limited | Transport & logistics | 2019 |
| KHS Estates Ltd | Real estate | 2021 |
| Kick & Connect CIC | Education | 2022 |
| Kieshamup Ltd | Health & social care | 2014 |