| Greenrapz Ltd | Wholesale & retail | 2026 |
| Greenstone Traditional Homes Ltd | Construction | 2023 |
| Greg Searle Rowing Ltd | Administrative & support | 2009 |
| Grey Close Management Company Limited | Households | 2016 |
| Grey Strategy Ltd | Professional & scientific | 2014 |
| Grown UPS Limited | Professional & scientific | 2024 |
| Growth Capital 1 Ltd | Professional & scientific | 2023 |
| Growthpivot Ltd | Professional & scientific | 2024 |
| Gsoc Ltd | Other services | 2022 |
| GT Wealth Management Limited | Financial services | 2002 |
| GTO H Ltd | Hospitality | 2018 |
| Guerilla Limited | Professional & scientific | 2000 |
| Guidesource Corporation Ltd | Professional & scientific | 2025 |
| Guthrie and Partners Ltd | Administrative & support | 2015 |
| GUY North Consulting Ltd | Professional & scientific | 2020 |
| Gwrc (RTM) Company Limited | Households | 2010 |
| H G H Partnership Limited | Real estate | 1998 |
| H&H Elite Developments Ltd | Construction | 2016 |
| Hackett Media Ltd | Information & communication | 2020 |
| Hagen Group Limited | Financial services | 2015 |
| Hailey Court Freehold Limited | Households | 2016 |
| Hairdressing Trading Limited | Other services | 2013 |
| Hairport Grooming Limited | Other services | 2024 |
| Halfpenny Lane Residents Limited | Households | 1994 |
| Hall Invest Limited | Education | 2024 |
| HAM Interiors Limited | Professional & scientific | 2010 |
| Hambleden Valley Joinery Ltd | Construction | 2026 |
| Hamilton Accountants Limited | Professional & scientific | 2012 |
| Hamilton Escapes Limited | Hospitality | 2020 |
| Hammersmith Gymnastics Club Ltd | Health & social care | 2010 |
| HAND2HEALTH Ltd | Health & social care | 2022 |
| Hands on Health Ltd | Health & social care | 2025 |
| Hanson Houses Ltd | Real estate | 2023 |
| Happen Productions Limited | Information & communication | 2017 |
| Happy Dog Property Developments Limited | Construction | 2022 |
| Happyoaks Ltd | Education | 2025 |
| Harescombe Court Residents Association (Beaconsfield) Limited | Households | 1963 |
| Harewood Travel Agencies Limited | Administrative & support | 1995 |
| Haringtons Payroll Ltd | Other services | 2009 |
| Harlequin Corporate Finance Limited | Professional & scientific | 1999 |
| Harlequin Estates Limited | Financial services | 2010 |
| Harlequin New Homes (Ascot) Limited | Construction | 2021 |
| Harlequin New Homes (Astrope) Limited | Construction | 2021 |
| Harlequin New Homes (Bagshot) Limited | Construction | 2021 |
| Harlequin New Homes (Cobham) Limited | Construction | 2023 |
| Harlequin New Homes (Dial Post) Limited | Construction | 2022 |
| Harlequin New Homes (Epsom) Limited | Construction | 2022 |
| Harlequin New Homes (Haslemere) Limited | Construction | 2022 |
| Harlequin New Homes (Horley) Limited | Construction | 2020 |
| Harlequin New Homes (Long Crendon) Limited | Construction | 2021 |
| Harlequin New Homes (Maidenhead 2) Limited | Construction | 2022 |
| Harlequin New Homes (Maidenhead 51) Limited | Construction | 2022 |
| Harlequin New Homes (Maidenhead) Limited | Construction | 2021 |
| Harlequin New Homes (Maresfield) Limited | Construction | 2020 |
| Harlequin New Homes (New Malden) Limited | Construction | 2023 |
| Harlequin New Homes (North Warnborough) Limited | Construction | 2022 |
| Harlequin New Homes (Reigate) Limited | Construction | 2021 |
| Harlequin New Homes (Shalden) Limited | Construction | 2024 |
| Harlequin New Homes (Tongham) Limited | Construction | 2021 |
| Harlequin New Homes (Toys Hill) Limited | Construction | 2022 |
| Harlequin New Homes (Warlingham) Limited | Construction | 2022 |
| Harlequin New Homes (Weald) Limited | Construction | 2021 |
| Harlequin New Homes (Weybridge) Limited | Construction | 2021 |
| Harlequin New Homes Limited | Construction | 2020 |
| Harleyford Aggregates Limited | Mining & quarrying | 1964 |
| Harleyford Estate Boat Sales and Brokerage Limited | Extraterritorial | 2010 |
| Harleyford Estate Chandlery and Accessories Limited | Extraterritorial | 2010 |
| Harleyford Estate Holiday Rentals Limited | Extraterritorial | 2010 |
| Harleyford Estate Holidays Limited | Extraterritorial | 2010 |
| Harleyford Estate Investments Ltd | Extraterritorial | 2010 |
| Harleyford Estate Limited | Real estate | 1950 |
| Harleyford Estate Marine Maintenance & Servicing Limited | Extraterritorial | 2010 |
| Harleyford Estate Moorings Limited | Extraterritorial | 2010 |
| Harleyford Estate Properties Limited | Extraterritorial | 2010 |
| Harleyford Estate Property Developments Limited | Extraterritorial | 2010 |
| Harleyford Estate Property Sales Limited | Extraterritorial | 2010 |
| Harleyford Estate Residential Limited | Extraterritorial | 2010 |
| Harleyford J Holdings Limited | Real estate | 2017 |
| Harleyford Leisure Enterprises Limited | Real estate | 1990 |
| Harris-Economy Limited | | 1972 |
| Harrow & Hope Limited | Manufacturing | 2003 |
| Harry Jameson Limited | Other services | 2009 |
| Harth Group Ltd | Information & communication | 2017 |
| Harvey CPM Ltd | Construction | 2015 |
| HARVEY2 Limited | Administrative & support | 2020 |
| Hashtag Sports Ltd | Wholesale & retail | 2022 |
| Hatfield Associates Ltd | Administrative & support | 2010 |
| Hatfield Homes Ltd | Real estate | 2023 |
| Hatton Golf Ltd | Arts & recreation | 2026 |
| Hatty Homes Ltd | Real estate | 2018 |
| Haunted Barn Limited | Professional & scientific | 2018 |
| Hayden Fine Art Limited | Wholesale & retail | 2023 |
| Hayscoaching Ltd | Education | 2023 |
| Haywood Court Residents Association Limited | Households | 1987 |
| Hazelwood Court (Maidenhead) M.C. Limited | Households | 2006 |
| Heatflow Plumbing & Heating Ltd | Construction | 2023 |
| Heather Barrett Limited | Professional & scientific | 2012 |
| Heighway (CAM) Holdings Limited | Financial services | 2025 |
| Heighway Associates Architects Limited | Professional & scientific | 2017 |
| Heighway Property Company Limited | Real estate | 2025 |