| Greenbloom Limited | Wholesale & retail | 1994 |
| Greener - Build Construction Limited | Construction | 2009 |
| Greenfield Estates Limited | Real estate | 2000 |
| Greengates Construction Ltd | Construction | 2018 |
| Greengates Groundworks Ltd | Construction | 2024 |
| Greengates Group Ltd | Administrative & support | 2024 |
| Greenhills Electric Limited | Construction | 1966 |
| Greenlink Mechanical Ltd | Construction | 2022 |
| Greensands Management Company Limited | Households | 2019 |
| Greenvale Property Investment Limited | Wholesale & retail | 2012 |
| Greenview Financial Services Limited | Information & communication | 2011 |
| Greenzayne Company Limited | Health & social care | 2012 |
| Gresta Construction Ltd | Construction | 2026 |
| Grey Oak Bespoke Joinery Ltd | Manufacturing | 2019 |
| Grey Rabbit Accountancy Limited | Professional & scientific | 2025 |
| Greys Hairdressing Limited | Other services | 2011 |
| Greystones Property Management Ltd | Households | 2014 |
| Gridline Contractors Ltd | Construction | 2026 |
| Grif Holdings Ltd | Real estate | 2022 |
| Griggs International Ltd | Education | 2016 |
| Grillnthrill Ltd | Hospitality | 2024 |
| Grocery Store Nation Ltd | Professional & scientific | 2015 |
| Groszek Hemel Ltd | Wholesale & retail | 2015 |
| GROUND2SUMMIT Ltd | Professional & scientific | 2025 |
| Grove Park Autos Ltd | Wholesale & retail | 2024 |
| Groveale Digital Ltd | Information & communication | 2017 |
| Grovehill Security & Support Services Ltd | Administrative & support | 2023 |
| Grovelands Heating Ltd | Construction | 2024 |
| Growe Talent Ltd | Administrative & support | 2025 |
| Growstone App Ltd | Information & communication | 2025 |
| Gryphon Creations Ltd | Professional & scientific | 2019 |
| GS Mobility Limited | Manufacturing | 2018 |
| GSA Cleaning Services Ltd | Construction | 2019 |
| Gsci Consultants Limited | Professional & scientific | 2010 |
| GSK Property Ltd | Construction | 2011 |
| GSM Innovate Properties Ltd | Real estate | 2018 |
| GST Psychiatry Ltd | Health & social care | 2026 |
| GSU Limited | Other services | 2006 |
| GSW Consultancy Limited | Administrative & support | 2020 |
| GSW GAS Ltd | Construction | 2023 |
| GT Property Management Services Ltd | Real estate | 2018 |
| GT(999) Limited | Information & communication | 2007 |
| Guangzhou Premier Plus Stationery Ltd | Real estate | 2011 |
| Guestifi Limited | Administrative & support | 2025 |
| Guraliuc Construction Ltd | Construction | 2017 |
| Gurgle Limited | Information & communication | 2007 |
| Gurney Construction Limited | Construction | 2012 |
| Guscott's Coaches Limited | Wholesale & retail | 1993 |
| Gusto Ltd | Hospitality | 2024 |
| GVS Prepaid Limited | Wholesale & retail | 2014 |
| GWB Property Venture Ltd | Real estate | 2026 |
| GWM Limited | Professional & scientific | 2023 |
| Gxngily Ltd | Information & communication | 2026 |
| Gyro Cosmos Ltd | Hospitality | 2024 |
| Gyro World Ltd | Hospitality | 2021 |
| H & a Rail Limited | Administrative & support | 2014 |
| H Building Solutions Limited | Construction | 2011 |
| H C H Operations Ltd | Professional & scientific | 2007 |
| H Heer Ltd | Information & communication | 2018 |
| H Hunt & Co Chartered Accountants Limited | Professional & scientific | 2025 |
| H Truman Ltd | Real estate | 2021 |
| H&A Infotech Limited | Information & communication | 2024 |
| H.E. Investments Limited | Real estate | 2003 |
| H.E.L. Machinery Limited | Financial services | 2025 |
| H.S. Management Limited | Other services | 1992 |
| H.S. Quantity Surveying Limited | Professional & scientific | 2006 |
| H.T. Prestige Builders Ltd | Construction | 2017 |
| H4 Aerospace (UK) Limited | Transport & logistics | 2001 |
| H4M Ltd | Hospitality | 2024 |
| H9 Technical Recruitment Holdings Ltd | Financial services | 2023 |
| H9 Technical Recruitment Limited | Administrative & support | 2016 |
| HA ANH Tuan Ltd | Other services | 2025 |
| Habibi Grill Ltd | Hospitality | 2025 |
| Haddenham Court Freehold Limited | Professional & scientific | 2012 |
| Hadley Grange Phase 4 Residents Management Company Limited | Households | 2023 |
| Hadley Lodge Management Co. Limited | Households | 1987 |
| Hadsworth Limited | Wholesale & retail | 1981 |
| Hafod Elfyn Management Company Ltd | Households | 2016 |
| Haines Court (Weybridge) Management Company Limited | Households | 2002 |
| Hairandglambyhannah Ltd | Other services | 2026 |
| Hairbyyasmin Ltd | Administrative & support | 2019 |
| Halcyon (Ashbourne Road) Management Company Limited | Households | 2006 |
| Halepost Limited | Real estate | 2013 |
| Half Penny Farm Foods Ltd | Agriculture & fishing | 2022 |
| Halkin House RTM Company Limited | Households | 2014 |
| Hallam Chase Management Limited | Households | 1986 |
| Halls Construction Ltd. | Construction | 2015 |
| Halls Estates Management Limited | Real estate | 2021 |
| Hallsdale Commercial Insurance Brokers Limited | Financial services | 2019 |
| Halvale Limited | Professional & scientific | 1985 |
| Halyards Residents Limited | Households | 2014 |
| Hamiltons Property Investments Ltd | Real estate | 2024 |
| Hamlet Park Management Company Limited | Households | 2023 |
| Hampden Fields Residents Management Company Limited | Households | 2025 |
| Hampden Gardens (Thame) Management Company Limited | Households | 2016 |
| Hanaa R Limited | Real estate | 2016 |
| Hanafan Autocare Ltd | Wholesale & retail | 2014 |
| Hand Car Wash London Road Ltd | Wholesale & retail | 2017 |
| Hand in Hand HR Ltd | Extraterritorial | 2020 |
| Handy for U Ltd | Professional & scientific | 2025 |