| Haversley Ltd | Administrative & support | 2010 |
| Havilah Gold Investment Limited | Real estate | 2021 |
| Hawk BIO Solutions Ltd | Water & waste | 2024 |
| Hawk Drainage and Groundworks Ltd | Water & waste | 2023 |
| Hawk Inns Limited | Administrative & support | 2020 |
| Hawk Property Investors Ltd | Real estate | 2021 |
| Hawkes Bay Trading Ltd | Manufacturing | 2025 |
| Hawkes Mill Associates Limited | Professional & scientific | 2017 |
| Hawkeye Design Ltd | Information & communication | 2011 |
| Hawkin Property Services Ltd | Real estate | 2020 |
| Hawkshead Catering Ltd | Hospitality | 2003 |
| Hawksmoor Services Ltd | Financial services | 2016 |
| Hawkstone Homes Limited | Real estate | 2019 |
| Hawra Cuts Ltd | Other services | 2026 |
| Hawthorns Retirement Living Limited | Health & social care | 2014 |
| HAX Barber Ltd | Other services | 2023 |
| Haybah Ltd | Wholesale & retail | 2025 |
| Hayden Road Management Company (Rushden) Limited | Households | 2024 |
| Hayes Race Engines Ltd | Manufacturing | 2024 |
| Hayes Taverns Limited | | 1989 |
| Hayfield Close Management Company Limited | Households | 2020 |
| Haykins Transport and Logistics Ltd | Transport & logistics | 2025 |
| Haysa Ltd | Health & social care | 2019 |
| Hayter Media Ltd | Information & communication | 2018 |
| Hayway Management Company Limited | Real estate | 1989 |
| HAZ Hospitality Ltd | Hospitality | 2025 |
| Hazard Heroes Northampton Ltd | Administrative & support | 2024 |
| Haze Supplies Ltd | Wholesale & retail | 2018 |
| Hazelback Estates Ltd | Real estate | 2002 |
| Hazelbrook Properties Ltd. | Real estate | 2001 |
| Hazelwood Associates Ltd | Professional & scientific | 2025 |
| HB and Co Developments Ltd | Construction | 2024 |
| HB Associates Ltd | Professional & scientific | 2026 |
| HB Books Limited | Professional & scientific | 2021 |
| HB DE Ltd | Construction | 2022 |
| HB Finishing Ltd | Construction | 2022 |
| HB Healthcare Limited | Professional & scientific | 2009 |
| HB London Properties Limited | Real estate | 2018 |
| HB Management Limited | Real estate | 2019 |
| HB Midway Limited | Construction | 2014 |
| HBB (J16) LLP | | 2014 |
| HBC Connect Holdings Ltd | Financial services | 2024 |
| HBC Connect Ltd | Construction | 2011 |
| Hbcet Ltd | Real estate | 2026 |
| HBG Northampton Limited | Construction | 2023 |
| Hbmj Investments Limited | Real estate | 2018 |
| HBP Property Investments Limited | Real estate | 2025 |
| HBZ Fresh Foods Ltd | Wholesale & retail | 2026 |
| HC 1287 Limited | Health & social care | 2017 |
| HC Five Star Ltd | Education | 2024 |
| HC Medical Services Ltd | Health & social care | 2024 |
| Hc&L Services Ltd | Construction | 2018 |
| HCB Plumbing and Bathrooms Limited | Construction | 2020 |
| HCC Solutions Co Ltd | Administrative & support | 2024 |
| HCD Consultants Limited | Professional & scientific | 2025 |
| HCE Enterprises Limited | Information & communication | 2025 |
| Hceo Ltd | Public administration | 2021 |
| Hcor Ltd | Wholesale & retail | 2022 |
| HD Fabrications Limited | Manufacturing | 2017 |
| HD Hire Ltd | Construction | 2022 |
| HD TEX Ltd | Manufacturing | 2019 |
| HE Fairs Ltd | Transport & logistics | 2024 |
| Headcases Golf Ltd | Manufacturing | 2026 |
| Headlamp Management Limited | Professional & scientific | 2003 |
| Headland Ventures Ltd | Hospitality | 2015 |
| Headlands Holiday Home for Dogs Ltd | Agriculture & fishing | 2023 |
| Headley George Computing Services Ltd | Information & communication | 2020 |
| Headline Construction Limited | Construction | 2021 |
| Headline Estate Limited | Real estate | 2026 |
| Heads of State Ltd | Other services | 2016 |
| Health Automated Ltd | Information & communication | 2023 |
| Health Care Response Ltd | Health & social care | 2009 |
| Health Corner (1) Ltd | Wholesale & retail | 2026 |
| Health Corner Limited | Wholesale & retail | 2021 |
| Health Health Care Limited | Health & social care | 2018 |
| Health Management Limited | Administrative & support | 2002 |
| Health Octopus Services Ltd | Health & social care | 2020 |
| Health Tech Talk Consultancy Ltd | Information & communication | 2023 |
| Healthcare Angels Ltd | Administrative & support | 2014 |
| Healthcare Dynamics Group Limited | Administrative & support | 2022 |
| Healthclino Limited | Health & social care | 2026 |
| Healthports Limited | Extraterritorial | 2012 |
| Healthtech Limited | Health & social care | 2011 |
| Healthy Nations Limited | Wholesale & retail | 2016 |
| Heart Kitchens Ltd. | Wholesale & retail | 2010 |
| Heart of England Holdings Limited | Professional & scientific | 2008 |
| Heart of England Motorhomes Limited | Wholesale & retail | 2002 |
| Heart of England Motorhomes Service Centre Ltd | Other services | 2006 |
| Heart of England Training Limited | Other services | 1971 |
| Heart of the Shires Tea Room Limited | Hospitality | 2025 |
| Heart Roof & Exterior Cleaning Ltd | Administrative & support | 2025 |
| Heart's of Young People CIC | Hospitality | 2022 |
| Hearth & James Ltd | Wholesale & retail | 2025 |
| Heartisan Fine Foods Limited | Administrative & support | 2018 |
| Heartwood Kitchen & Furniture Co. Limited | Manufacturing | 2002 |
| Hearty Cuisine Ltd | Hospitality | 2022 |
| Heat Source Plumbing, Heating & Renewable Energy Limited | Construction | 2016 |
| Heat Treatments (Northampton) Limited | Manufacturing | 1989 |
| Heatex GAS Solutions Ltd | Construction | 2026 |
| Heath Glazing Ltd | Construction | 2018 |