| Hartley Heating & Plumbing Ltd | Construction | 2017 |
| Harts Holiday Camps Limited | Hospitality | 1991 |
| Harts Holiday Village Limited | Hospitality | 1951 |
| Hasbex Ltd | Extraterritorial | 2025 |
| Hastings (US) Limited | Professional & scientific | 2020 |
| Hastings Court (Bexhill) Management Company Limited | Households | 2015 |
| Hastings FAT Tuesday C.I.C. | Arts & recreation | 2014 |
| Hastings Fringe Comedy Festival Ltd | Arts & recreation | 2019 |
| Hastings Group Holdings Limited | Professional & scientific | 2015 |
| Hastings Scaffolding Ltd | Construction | 2024 |
| Hatbase Limited | Households | 1992 |
| Haushold Limited | Financial services | 2023 |
| Hayward Mortgage Services Ltd | Financial services | 2023 |
| Hbmf Limited | Arts & recreation | 2010 |
| Head on Board CIC | Health & social care | 2022 |
| Heartbridge Healthcare Ltd | Real estate | 2015 |
| Heat Master Services Ltd | Construction | 2025 |
| Heathcroft Limited | Administrative & support | 2002 |
| Helena Court Residents Association Limited | Households | 1991 |
| Hepworth Estates Ltd | Real estate | 2021 |
| Heron Film Ltd | Information & communication | 2021 |
| Herts Lung Clinic Limited | Health & social care | 2022 |
| HGC2021 Ltd | Wholesale & retail | 2021 |
| HH Capital Investments Limited | Professional & scientific | 2024 |
| Hiauk Limited | Construction | 2002 |
| Hifiguy Limited | Wholesale & retail | 2012 |
| High Perform Limited | Professional & scientific | 1994 |
| Highgrove Residents Association Limited | Other services | 2003 |
| Highlands Gardens Investment Company Limited | Real estate | 2004 |
| Highwood House Limited | Households | 1998 |
| Highwoods Court (Bexhill) Limited | Other services | 2006 |
| Hill Pocknell Developments Limited | Construction | 2018 |
| Hillborough Management (Bexhill) Limited | Households | 1990 |
| Hillborough Properties Limited | Construction | 1997 |
| Hills Property Services & Contractors Limited | Construction | 2024 |
| Hindscray Limited | Construction | 1977 |
| Historic Enterprises Ltd | Wholesale & retail | 2025 |
| Hive and Host Ltd | Information & communication | 2016 |
| Hive Hub London Limited | Information & communication | 2016 |
| Hocc Ltd. | Information & communication | 2019 |
| Hola Tiles Ltd | Construction | 2024 |
| Holistic Care Innovations Ltd | Administrative & support | 2022 |
| Holistic Care Vision Ltd | Health & social care | 2023 |
| Holly Rose Group Ltd | Financial services | 2024 |
| Holmes Decorating Contractors Ltd | Construction | 2025 |
| Home From Home AIV Limited | Education | 2020 |
| Home From Home Student Stays Limited | Administrative & support | 2025 |
| Home Road Investments Limited | Real estate | 2024 |
| Home Staging Solutions Ltd | Real estate | 2025 |
| Home-School Tutoring Sussex and Kent Ltd | Education | 2022 |
| Home-School Tutoring Wiltshire Ltd | Education | 2024 |
| Honos Logistics Ltd | Transport & logistics | 2025 |
| Hooly Furniture Limited | Extraterritorial | 2022 |
| Hoon Rebels Ltd | Wholesale & retail | 2021 |
| Hosier & Sons Property Limited | Real estate | 2025 |
| House of Darts Ltd | Other services | 2023 |
| Howell Graciotti Ltd | Information & communication | 2018 |
| Hoyden Limited | Real estate | 1992 |
| Hprj Nicholls Ltd | Real estate | 2025 |
| HPY Eastbourne Ltd | Arts & recreation | 2021 |
| Hsnet Ltd | Professional & scientific | 2000 |
| Hurst Court Gardens Limited | Other services | 2017 |
| Husl Limited | Real estate | 2022 |
| HV Renewables Ltd | Administrative & support | 2022 |
| Hydroguard Roofing and Building Ltd | Construction | 2025 |
| I D C Investments Limited | Real estate | 2019 |
| I Delta Heating and Electrical Specialist Limited | Energy | 2019 |
| I W Management Limited | Professional & scientific | 2016 |
| I-Survey (South East) Limited | Professional & scientific | 2013 |
| Iain Maitland Limited | Information & communication | 2003 |
| Ibuild (Sussex) Limited | Construction | 2011 |
| Icarus Trade Company Limited | Financial services | 2014 |
| Ideal Painters & Decorators Ltd | Construction | 2019 |
| IJA (Berkshire) Ltd | Real estate | 2025 |
| IMG Operations Ltd | Professional & scientific | 2022 |
| Impact Marketing Consultancy Limited | Professional & scientific | 2024 |
| Imperial Healthcare (UK) Ltd | Health & social care | 2011 |
| Impraimcare Limited | Health & social care | 2021 |
| IN Phase Management Limited | Professional & scientific | 2002 |
| Inavent Ltd | Other services | 2025 |
| Inbreath Limited | Extraterritorial | 2016 |
| Independent Safety Consultancy Ltd | Professional & scientific | 2020 |
| Indesign Furniture Limited | Wholesale & retail | 2009 |
| Inertia PM Limited | Professional & scientific | 2025 |
| Inox Technical Lighting Limited | Construction | 2003 |
| Insley Court Residents Company Limited | Households | 1989 |
| Inspirationelle Foundation | Professional & scientific | 2018 |
| Inspired Intentions Ltd | Professional & scientific | 2024 |
| Inspiring Potential Limited | Education | 2023 |
| Interlagos Limited | Information & communication | 2003 |
| International Telecommunications and Space Systems Itss Limited | Information & communication | 2011 |
| International Wrestling Network Limited | Arts & recreation | 2019 |
| Into IT Support Ltd | Information & communication | 2017 |
| Intracrels (Bexhill Management) Limited | Households | 1961 |
| Italian Way (Hastings) Limited | Hospitality | 2013 |
| Italian Way Limited | Real estate | 1961 |
| Itranslation Service Limited | Professional & scientific | 2017 |
| Itsfromat Limited | Information & communication | 2000 |
| J & a Guardian Ltd | Real estate | 2023 |
| J H Inns Ltd | Hospitality | 2019 |