| GB Solutions Limited | Construction | 2018 |
| Gbspp Limited | Health & social care | 2016 |
| GDB Signals Ltd | Professional & scientific | 2024 |
| GEC Services (Essex) Ltd | Construction | 2022 |
| Gems Pet Products Limited | Wholesale & retail | 2014 |
| Gentle Currents Ltd | Manufacturing | 2025 |
| Gfymm Ltd | Financial services | 2025 |
| Ggsk Ceilings Limited | Construction | 2005 |
| GH Piling & Welding Services Limited | Construction | 2015 |
| Ghag Shopfront Limited | Construction | 2026 |
| GI Refurbishments Ltd | Construction | 2025 |
| Giffards Primary School | Education | 2014 |
| Giftinglove Ltd | Wholesale & retail | 2025 |
| Giggles & Grins Home Nursery Ltd | Education | 2024 |
| Gimar Services Limited | Administrative & support | 2018 |
| Girty Holdings Limited | Real estate | 2010 |
| GJS Plumbing & Heating Services Ltd | Construction | 2015 |
| GKP Formwork Ltd | Construction | 2022 |
| Glass Rooms Limited | Construction | 2005 |
| Glenward Builders Ltd | Construction | 1998 |
| Globe Security Systems Limited | Construction | 2009 |
| Glow Intense Limited | Real estate | 2016 |
| Go Travel Worldwide Ltd | Administrative & support | 2022 |
| Gohanz Ltd | Construction | 2021 |
| Golden Years Home Maintenance Ltd | Construction | 2025 |
| Golds Tiling Limited | Construction | 2018 |
| Goldsmith & Sons (UK) Ltd | Construction | 2019 |
| Good MAN Food Ltd | Hospitality | 2025 |
| Goodair Limited | Energy | 2008 |
| Graces Health Ltd | Health & social care | 2024 |
| Graham James Primary Academy | Education | 2013 |
| Grant Compliance Services UK Ltd | Professional & scientific | 2025 |
| Gravanbank Flooring Services Limited | Construction | 2016 |
| Grech Wealth Management Ltd | Professional & scientific | 2020 |
| Green CUT Solutions Ltd | Administrative & support | 2025 |
| Green Junction Ltd | Information & communication | 2025 |
| Green Kent Limited | Real estate | 2020 |
| Green Palace Ltd | Hospitality | 2018 |
| Greenacre Water Treatment Consultancy Ltd | Professional & scientific | 2025 |
| Greenlands United Limited | Real estate | 2019 |
| Greenline Land Services Limited | Administrative & support | 2026 |
| Greycluster Software Ltd | Information & communication | 2024 |
| GT Property Sourcing and Investments Limited | Real estate | 2022 |
| GTO Distribution Limited | Wholesale & retail | 2003 |
| Hair Kemistry Limited | Other services | 2024 |
| Halil Limited | Hospitality | 2023 |
| Hall Consultancy Limited | Professional & scientific | 2012 |
| Halls Specialised Shot Blasting Services Ltd | Construction | 2024 |
| Handyman First Ltd | Construction | 2026 |
| Hannah Davis Homes Ltd | Real estate | 2024 |
| Hardie Park Projects C.I.C. | Wholesale & retail | 2012 |
| Harrison Maintenance Limited | Construction | 2015 |
| HDF Solutions Ltd | Transport & logistics | 2025 |
| Headstart Daycare Limited | Education | 2012 |
| Healview Recruitment Limited | Health & social care | 2018 |
| Hedge London Limited | Construction | 2007 |
| Help Consultancy Limited | Professional & scientific | 2025 |
| Heritage of Grace Outreach | Health & social care | 2013 |
| Hettyj Construction Consultancy Ltd | Professional & scientific | 2022 |
| HFB Properties Ltd | Real estate | 2020 |
| High Class Landscapers Ltd | Administrative & support | 2025 |
| Highland Associates Ltd | Construction | 2011 |
| Hireco (TL) Limited | Transport & logistics | 1998 |
| Hirst CX Ltd | Professional & scientific | 2024 |
| HLC Consultants Limited | Financial services | 2025 |
| Hollieslocks Salon Limited | Extraterritorial | 2022 |
| Holloway Home Developments Ltd | Construction | 2017 |
| Homestead Care Homes Limited | Health & social care | 2003 |
| Honeyz Catering Services Limited | Hospitality | 2013 |
| Hope Green Ltd | Hospitality | 2025 |
| Horiho Property Limited | Real estate | 2024 |
| Horiho UK Limited | Hospitality | 2016 |
| Horndon Audio Ltd | Administrative & support | 2022 |
| Horndon Property Ltd | Real estate | 2025 |
| Hotdigitalonline Limited | Information & communication | 2015 |
| House Harmony Ltd | Administrative & support | 2025 |
| House of Bubu Ltd | Wholesale & retail | 2024 |
| HQ Scaffolding Ltd | Construction | 2020 |
| Hugh MAY & Co Limited | Financial services | 2011 |
| Husne 2019 Ltd | Hospitality | 2019 |
| Hustle Eats Ltd | Hospitality | 2013 |
| Hygienia Immaculate Limited | Administrative & support | 2026 |
| Hyper & Vague Limited | Administrative & support | 2008 |
| I C T Express Limited | Transport & logistics | 1997 |
| I Designs Limited | Professional & scientific | 2003 |
| I P Engineering Services Limited | Administrative & support | 1995 |
| IAN Boatman Mechanical Limited | Construction | 2014 |
| IAN Firth Limited | Administrative & support | 1999 |
| IAN Sexton Consultants Ltd | Professional & scientific | 2016 |
| IBF London Ltd | Real estate | 2024 |
| Icarus Property Management Ltd | Households | 2023 |
| Icon Range Homes LLP | | 2018 |
| Icon Range Limited | Real estate | 2020 |
| Icon Range Properties LLP | | 2017 |
| Icon Roots Limited | Construction | 2017 |
| Icon Serviced Apartments LLP | | 2016 |
| Icon T4 Range Limited | Hospitality | 2014 |
| Icon the Green Limited | Real estate | 2017 |
| Idee Digital Limited | Administrative & support | 2015 |
| Identity Pixel Design Ltd | Information & communication | 2022 |