| Hayzed Digital Solutions Ltd | Information & communication | 2026 |
| HBH Bars and Pubs Ltd | Hospitality | 2018 |
| HD Gifts Ltd | Wholesale & retail | 2021 |
| Headhunters Alliance Ltd | Administrative & support | 2024 |
| Health @ Handleys Ltd | Hospitality | 2025 |
| Healthier Choice Ltd | Wholesale & retail | 2018 |
| Heard About SAM Limited | Professional & scientific | 2021 |
| Heard About Take Offs Ltd | Professional & scientific | 2025 |
| Heart of Portsmouth Boxing Academy CIC | Arts & recreation | 2021 |
| Heartlands Community Voice | Other services | 2008 |
| Heat Co GAS Limited | Construction | 2024 |
| Heat Co Plumbing & Heating Limited | Construction | 2023 |
| Heatwavegrill Ltd | Hospitality | 2024 |
| Helen Kane HCM Limited | Professional & scientific | 2023 |
| Helena Lodge Management Company Limited | Real estate | 2002 |
| Helping Hands Carers Limited | Health & social care | 2025 |
| Henarch Properties Ltd | Real estate | 2016 |
| Henderson AI Ltd | Professional & scientific | 2024 |
| Heraghty and Lumb Limited | Manufacturing | 2008 |
| Herbwise Ltd | Real estate | 2006 |
| Hercanos Ltd | Extraterritorial | 2015 |
| Herculean Security Ltd | Other services | 2018 |
| Hereford Court RTM Company Limited | Households | 2010 |
| Hereford House Management (Southsea) Limited | Households | 1999 |
| High Reach Cleaning (HRC) Limited | Administrative & support | 2019 |
| High Voltage Hutch Ltd | Construction | 2020 |
| Highland Management Limited | Households | 2017 |
| Highland Mini Market Limited | Wholesale & retail | 2022 |
| Hillomatic Music Ltd | Administrative & support | 2025 |
| Hillrise Property Partners Ltd | Construction | 2025 |
| Hirado Limited | Manufacturing | 2020 |
| HIS Glory Food Store Limited | Hospitality | 2012 |
| Hitw (Southsea) Limited | Hospitality | 2013 |
| Hive 2 Ltd | Real estate | 2024 |
| Hive Estates Management Ltd | Real estate | 2025 |
| Hive I Ltd | Real estate | 2023 |
| Hive Southsea Limited | Hospitality | 2022 |
| Hjch Limited | Information & communication | 2026 |
| HKC Vodka Bar Limited | Arts & recreation | 2023 |
| HL Marketing Ltd | Professional & scientific | 2018 |
| Holiday Home & Leisure Services Limited | Hospitality | 2013 |
| Hollingley Technology Limited | Information & communication | 2025 |
| Holloway Motors Southsea Ltd | Wholesale & retail | 2024 |
| Hollyhock Books Ltd | Information & communication | 2025 |
| Holmes Flooring Services Ltd | Construction | 2013 |
| Holt Alarms and Electrical Contractors Ltd | Administrative & support | 2010 |
| Home From Home by the Sea Ltd | Hospitality | 2025 |
| Home of HR Limited | Administrative & support | 2018 |
| Home to School Transport Limited | Transport & logistics | 2021 |
| Home View Roofing Ltd | Construction | 2025 |
| Homes From Holme Limited | Real estate | 2002 |
| Honeycomb Integrated Marketing Ltd | Professional & scientific | 2019 |
| Honeywood Mews Management Company Limited | Households | 2020 |
| Hookline and Chips Ltd | Hospitality | 2016 |
| HOP & Glory Pubs Ltd | Hospitality | 2025 |
| Hope (Portsmouth) | Health & social care | 2007 |
| Hot Walls + Ltd | Wholesale & retail | 2023 |
| Hotkey Professional Services Ltd | Information & communication | 2013 |
| House of Langstone Limited | Professional & scientific | 2018 |
| Howards Way Estate Management Limited | Households | 2021 |
| Howieserv Ltd | Professional & scientific | 2024 |
| HR Distributors Ltd | Wholesale & retail | 2025 |
| Hrmc Limited | Households | 2004 |
| Hub Club Homes Ltd | Administrative & support | 2017 |
| Hughes Power Solutions Ltd | Construction | 2018 |
| Huis Southsea Ltd | Hospitality | 2016 |
| Human Systems Leadership Ltd | Professional & scientific | 2023 |
| Humphries Murphy Electrical Services Ltd | Construction | 2023 |
| Hunky Dorey Ltd | Real estate | 2003 |
| Hunter & Grey's Ltd | Wholesale & retail | 2023 |
| Huxley Properties Ltd | Real estate | 2024 |
| HWA Telecoms Limited | Information & communication | 2015 |
| Hybrid Racing Platform Ltd | Information & communication | 2026 |
| Hythe Hand Car Wash Ltd | Administrative & support | 2020 |
| I J Murray Associates Limited | Professional & scientific | 2004 |
| I Love to Learn Havant LLP | | 2024 |
| I Love to Learn Liphook LLP | | 2026 |
| I Love to Learn Portsmouth LLP | | 2024 |
| I Thomson Holdings LLP | | 2023 |
| I&C Emporium Limited | Wholesale & retail | 2025 |
| I&C Trans Ltd | Wholesale & retail | 2016 |
| I'N'I Games Ltd | Manufacturing | 2026 |
| I-Glaze Commercial Ltd | Construction | 2025 |
| Iain Pollard Ltd | Professional & scientific | 2012 |
| IB Vision Ltd | Information & communication | 2026 |
| Ibrowbar Limited | Other services | 2020 |
| Ibuild Management Services Limited | Construction | 2016 |
| IC Southsea Ltd | Hospitality | 2019 |
| Icac Limited | Information & communication | 2016 |
| Ice BT Ltd | Construction | 2006 |
| Ice Electrical Contractors Holdings Limited | Construction | 2010 |
| Ice Line Agency Limited | Professional & scientific | 2022 |
| Icebergs Pompey TM Ltd | Hospitality | 2025 |
| ICG Acadamy Ltd | Professional & scientific | 2025 |
| Icloud Telecom Ltd | Information & communication | 2019 |
| IDB Property Ltd | Households | 2024 |
| Idea Tech UK Ltd | Wholesale & retail | 2023 |
| IGB Property Holdings Ltd | Real estate | 2025 |
| Ihelp Gadget Repairs Ltd | Wholesale & retail | 2020 |
| Ihsan Ecommerce Ltd | Wholesale & retail | 2026 |