| Halfway Group Ltd | Hospitality | 2026 |
| Halfway Homes Limited | Hospitality | 2022 |
| Halifax Import and Export Limited | Other services | 2006 |
| Halny Tech Ltd | Information & communication | 2021 |
| Halo Pro Ltd | Construction | 2025 |
| Halt Alarms Limited | Administrative & support | 2002 |
| Hamilton Home and Living Limited | Construction | 2017 |
| Hampden Supply Ltd | Wholesale & retail | 2020 |
| Hampden UK Holdings Ltd | Financial services | 2020 |
| Hand Media International Limited | Information & communication | 2017 |
| Hand Media Management Services Limited | Information & communication | 2010 |
| Hand Polishing Services Ltd | Administrative & support | 2025 |
| Handley's of Dartford Ltd | Administrative & support | 2007 |
| Handy AV Limited | Information & communication | 2002 |
| Hanover 7 Limited | Real estate | 2025 |
| Hanover 77 Limited | Real estate | 2025 |
| Happy Days by ANI Ltd | Hospitality | 2024 |
| Happy Forest Projects Ltd | Manufacturing | 2010 |
| Harc Partners Limited | Professional & scientific | 2016 |
| Hards Housing Ltd | Real estate | 2024 |
| Hards Refurbishments Ltd | Construction | 2020 |
| Hardy Creative Ltd | Information & communication | 2018 |
| Hare Plastering & Maintenance Limited | Construction | 2017 |
| Harland Avenue (Sidcup) Management Company Limited | Households | 2013 |
| Harland Search Ltd | Professional & scientific | 2020 |
| Harley Fabrications Limited | Other services | 2014 |
| Harley Street Speech Therapy Ltd | Health & social care | 2018 |
| Harnzee Limited | Real estate | 2023 |
| Harp Freehold Limited | Real estate | 2025 |
| Harris Kensington Advisory Ltd | Administrative & support | 2023 |
| Harry Thompson Marketing Ltd | Professional & scientific | 2023 |
| Hartley Developments & Construction Limited | Administrative & support | 2007 |
| Harvestflow Ltd | Hospitality | 2021 |
| Harvey Fraser Properties Limited | Real estate | 2020 |
| Harvey James Limited | Professional & scientific | 2022 |
| Hasel Group Ltd | Hospitality | 2026 |
| Hatherley Developments Limited | Real estate | 2010 |
| Hatherley Freehold Limited | Administrative & support | 2007 |
| Hatherlow House Management Limited | Administrative & support | 2000 |
| Haven Grove Limited | Health & social care | 2025 |
| Havenly Services Ltd | Professional & scientific | 2026 |
| Hawkey Properties Limited | Construction | 2006 |
| Hays Carpentry and Construction Ltd | Construction | 2025 |
| Hayward Developments (London) Limited | Construction | 2021 |
| Hazi Limited | Hospitality | 2025 |
| HB Salon Ltd | Other services | 2021 |
| HBJ Mechanical Services Limited | Construction | 2025 |
| HCH Plant Hire Limited | Administrative & support | 2018 |
| HD Design & Management Ltd | Professional & scientific | 2023 |
| Hdna Properties Limited | Real estate | 2022 |
| Head Projects Limited | Administrative & support | 2013 |
| Headriver Ltd | Manufacturing | 2022 |
| Heal of Hand Ltd | Other services | 2024 |
| Heart of Town II Limited | Professional & scientific | 2025 |
| Heart of Town Investments Ltd | Financial services | 2021 |
| Heart of Town Ltd | Real estate | 2019 |
| Heart Teaching Ltd | Education | 2015 |
| Heat Pump Group Limited | Construction | 2024 |
| Heating Services Limited | Manufacturing | 2008 |
| Helios Homes Limited | Real estate | 2019 |
| Helios Sidcup Limited | Other services | 2025 |
| Hellberg Properties Limited | Real estate | 2016 |
| Hempenstall Construction Ltd | Construction | 2015 |
| Henbury Construction Services Limited | Construction | 2025 |
| Henhall Limited | Information & communication | 2025 |
| Henos Services Ltd | Health & social care | 2019 |
| Henri-Taylor Heating Solutions Limited | Construction | 2019 |
| Henry James Solutions Limited | Administrative & support | 2019 |
| Hensi Properties Ltd | Real estate | 2024 |
| Henty Construction South East Limited | Administrative & support | 2011 |
| Heraquest Ltd | Professional & scientific | 2023 |
| Herholdt Chiropractic Limited | Health & social care | 2011 |
| Heritage & Home SW Limited | Administrative & support | 2024 |
| Heritage GAS Services Ltd | Construction | 2013 |
| HET Food Limited | Hospitality | 2024 |
| Hexahedron Ventures Limited | Professional & scientific | 2025 |
| Hexblocks Technologies Limited | Information & communication | 2025 |
| HH Climate Solutions Ltd | Construction | 2024 |
| HH Web Design Limited | Professional & scientific | 2022 |
| Hibbert Housing Ltd | Real estate | 2025 |
| Hibbtech Limited | Information & communication | 2025 |
| High Top Roofing & Property Maintenance Ltd | Administrative & support | 2021 |
| High Weald Heritage Limited | Construction | 2021 |
| Higham Vision Limited | Construction | 2011 |
| Highgrove P & R Ltd | Real estate | 2022 |
| Highway Express Limited | Administrative & support | 1995 |
| Hiking Hound Ltd | Wholesale & retail | 2022 |
| Hilditch & Key (Holdings) Limited | Professional & scientific | 1960 |
| Hilditch & Key Limited | Wholesale & retail | 1967 |
| Hill Top Construction South East Limited | Construction | 2016 |
| Hine Construction Limited | Construction | 2010 |
| Hire Access Limited | Administrative & support | 2014 |
| Histriónica Ltd | Information & communication | 2020 |
| Hitta Limited | Arts & recreation | 2026 |
| Hive (Richmond) Ltd | Administrative & support | 2023 |
| HLI Projects Limited | Construction | 2023 |
| HM Diligence Limited | Professional & scientific | 2024 |
| HM Plumbing & Heating Limited | Construction | 2018 |
| HM Procurement Services Limited | Professional & scientific | 2008 |
| HMT Rubbaglas Limited | Manufacturing | 2001 |