| Hadleigh Nails & Beauty Ltd | Other services | 2019 |
| Hadleigh News Limited | Wholesale & retail | 2023 |
| Hadleigh Patterns Limited | Extraterritorial | 1972 |
| Hadleigh Physiotherapy Limited | Health & social care | 2013 |
| Hadleigh Private Hire Cars Limited | Transport & logistics | 2012 |
| Hadleigh Road Estate Limited | Households | 1988 |
| Hadleigh Road Sewerage Plant Limited | Water & waste | 2008 |
| Hadley Apennine Limited | Professional & scientific | 2021 |
| Hadlil Limited | Wholesale & retail | 2025 |
| Hadron Dinghies Limited | Manufacturing | 2015 |
| Haffenden Hair Limited | Other services | 2011 |
| Hafnia Energy Global Limited | Energy | 2021 |
| Hagag Limited | Agriculture & fishing | 2016 |
| Hague Global Limited | Wholesale & retail | 2016 |
| Hail Air Conditioning Ltd | Energy | 2016 |
| Hair Ministry Limited | Other services | 2003 |
| Hair-Tech Ipswich Ltd | Wholesale & retail | 2019 |
| Hairhart Limited | Other services | 2015 |
| Hairlistic Kesgrave Limited | Other services | 2025 |
| Hairluzz Limited | Other services | 2022 |
| Hako Style Ltd | Wholesale & retail | 2020 |
| Hakran Limited | Hospitality | 2022 |
| Hale and Hearty Ltd | Health & social care | 2023 |
| Hale Being Care Ltd | Health & social care | 2025 |
| Halid 74-TRANS Ltd | Transport & logistics | 2017 |
| Hallwood Training Services Limited | Administrative & support | 2008 |
| Halo Dental Practice Ltd | Health & social care | 2023 |
| Halo Entertainment Ltd | Arts & recreation | 2018 |
| Hamford Mechanical Services Ltd | Construction | 2013 |
| Hamilton Smith (Needham Market) Limited | Real estate | 1997 |
| Hamilton Smith Ipswich Limited | Real estate | 2021 |
| Hamilton Stocks Ltd | Manufacturing | 2026 |
| Hamiltons Driver Training Limited | Education | 2014 |
| Hamlet Abbey Ltd | Administrative & support | 2022 |
| Hamlet J (NO.1) Management Company Limited | Households | 1982 |
| Hamlet J (NO.2) Management Company Limited | Households | 1982 |
| Hamlet J (NO.3) Management Company Limited | Households | 1982 |
| Hammer Above Ltd | Manufacturing | 2025 |
| Hammer and Ledger Tax Limited | Professional & scientific | 2026 |
| Hammond Autoserv Limited | Wholesale & retail | 2007 |
| Hammond Road Garage Limited | Wholesale & retail | 2008 |
| Hammond Storage Ltd | Other services | 2018 |
| Hampi Solutions Ltd | Professional & scientific | 2025 |
| Hampstead Heath Estates 5 Limited | Real estate | 2022 |
| Hampstead Heath Estates 7 Limited | Real estate | 2022 |
| Hampstead Heath Estates Limited | Real estate | 2020 |
| Hand-Held Videos Ltd | Information & communication | 2023 |
| Handcrafted ME Ltd | Wholesale & retail | 2023 |
| Handfast Marine Ltd | Administrative & support | 2015 |
| Handford Homes Limited | Professional & scientific | 2017 |
| Handford Lettings Limited | Real estate | 2018 |
| Handley Consultancy Ltd | Professional & scientific | 2024 |
| Haneen Alsham Ltd | Wholesale & retail | 2024 |
| HANGER39 Ltd | Wholesale & retail | 2008 |
| Hani Akar Limited | Other services | 2018 |
| Hanks Hairdressing Limited | Other services | 2012 |
| Hanks Vegan Holdings Limited | Hospitality | 2019 |
| Hannah Cordle Consulting Limited | Professional & scientific | 2024 |
| Hannah Louise Ltd | Other services | 2024 |
| Hans Grill Limited | Administrative & support | 2017 |
| Hanwell Associates Ltd | Professional & scientific | 2024 |
| Hapi Build Ltd | Construction | 2021 |
| Happenings Community C.I.C. | Information & communication | 2025 |
| Happy Babies Ltd | Arts & recreation | 2023 |
| Happy Cadance Ltd | Information & communication | 2025 |
| Happy Go Doggy Pet Care Ltd | Other services | 2024 |
| Happy Hits Radio & Media CIC | Information & communication | 2026 |
| Happy Hour Cocktail Bars Limited | Hospitality | 2015 |
| Happy House Ipswich Ltd | Hospitality | 2026 |
| Happy Trails Dog Walking Limited | Other services | 2018 |
| Happy Vacations Limited | Hospitality | 2026 |
| Happy Valley Coffee Limited | Manufacturing | 2024 |
| HAR Trans Ltd | Transport & logistics | 2021 |
| Harbico Limited | Wholesale & retail | 2026 |
| Harbor and Haven Ltd | Professional & scientific | 2025 |
| Harbour Deli Limited | Hospitality | 2018 |
| Harbour Herring Co Limited | Wholesale & retail | 2024 |
| Harbour Lights Restaurant Limited | Real estate | 2004 |
| Hardball Smokehouse Bar and Grill Ltd | Hospitality | 2023 |
| Hardcore Transport Ltd | Transport & logistics | 2024 |
| Hardi's Cuts Ltd | Other services | 2025 |
| Harding Davey Properties Limited | Real estate | 2022 |
| Hardman Oakley Ltd | Construction | 2017 |
| Hardwicke Services Ltd | Construction | 2021 |
| Hardy Collectibles Ltd | Manufacturing | 2026 |
| Harian Leisure (Ipswich) Ltd. | Transport & logistics | 1995 |
| Harian Leisure (Woodbridge) Limited | Transport & logistics | 2009 |
| Harkstead Road Management Company Limited | Households | 2022 |
| Harlequin Models Limited | Arts & recreation | 2013 |
| Harley Contemporary Homes Ltd | Real estate | 2022 |
| Harmonious Group Ltd | Wholesale & retail | 2020 |
| Harmonious Gym Ltd | Arts & recreation | 2026 |
| Harmonious Healing Ltd | Health & social care | 2020 |
| Harmoniouscurve Ltd | Hospitality | 2025 |
| Harp Property Investing Limited | Real estate | 2017 |
| Harriet Cadman Consultancy Services Limited | Professional & scientific | 2017 |
| Harriet Jane Advertising Ltd | Professional & scientific | 2023 |
| Harris + Moore Ltd | Construction | 2022 |
| Harris Bookkeeping & Accountancy Services Ltd | Professional & scientific | 2024 |
| Harris Property Investment Solution Ltd | Real estate | 2024 |