| High Pixel Media Ltd | Professional & scientific | 2024 |
| Highcroft Construction Limited | Construction | 2019 |
| Highdown Construction Limited | Construction | 2011 |
| Higher and Professional Education Associates Ltd | Professional & scientific | 2019 |
| Highgrove Dental Care Limited | Health & social care | 2014 |
| Highmount Properties Limited | Real estate | 2011 |
| Highspeed Ferries Limited | Transport & logistics | 2010 |
| Highstone Solutions Limited | Information & communication | 2000 |
| Hightower Video Ltd | Information & communication | 2019 |
| Higton Dental Courses Ltd | Education | 2022 |
| Higton Dental Ltd | Health & social care | 2018 |
| Hiley Hospitality Consulting Limited | Professional & scientific | 2025 |
| Hilight Semiconductor Limited | Professional & scientific | 2012 |
| Hill Bros (Brighton) Ltd | Construction | 2020 |
| Hill Recruitment Ltd | Administrative & support | 2020 |
| Hillingar Limited | Public administration | 2008 |
| Hills & Downs Property Preservation Ltd | Administrative & support | 2016 |
| Hillsfx Limited | Information & communication | 2007 |
| Hilsea Heights Management Company Limited | Households | 2003 |
| Hilton Hood Properties Ltd | Other services | 2016 |
| Himal Natural Fibres Ltd | Wholesale & retail | 2017 |
| Hippolyte Healing Limited | Other services | 2017 |
| Hipster Brighton Holiday Rental Limited | Real estate | 2022 |
| HIT and Run Sport Ltd | Wholesale & retail | 2015 |
| Hivebook Limited | Information & communication | 2015 |
| HJB Rubbish Limited | Water & waste | 2026 |
| HJF International Limited | Professional & scientific | 2025 |
| HJG Asset Holdings Ltd | Real estate | 2021 |
| HL MOT and Van Centre Ltd | Wholesale & retail | 2020 |
| HLI 3 Ltd | Real estate | 2018 |
| HLI SUB Co Ltd | Real estate | 2022 |
| HLM Communications Ltd | Professional & scientific | 2022 |
| HM Rentals Limited | Real estate | 2020 |
| HMS16 Limited | Administrative & support | 2016 |
| HN Quality Ltd. | Manufacturing | 2016 |
| HNW Advisor Group Limited | Information & communication | 2017 |
| HO15 Ltd | Arts & recreation | 2024 |
| Hoagy Productions Limited | Information & communication | 2012 |
| Hobi Cafes Ltd | Hospitality | 2020 |
| Hoeford Research Limited | Professional & scientific | 2021 |
| Hoffman Baird Financial Services Limited | Professional & scientific | 2011 |
| Hoffman Baird Ltd | Professional & scientific | 2000 |
| Holdaway Home Tutoring Limited | Education | 2011 |
| Holdmybag Ltd | Transport & logistics | 2025 |
| Holgate Investments (Commercial) Limited | Real estate | 2009 |
| Holiday Weather Limited | Administrative & support | 2011 |
| Holland Park Consulting London Ltd | Hospitality | 2018 |
| Holland Road (Hove) Limited | Households | 2012 |
| Holland Road Baptist Church Trust | Other services | 2010 |
| Hollbridge Limited | Administrative & support | 2013 |
| Hollbridge Ventures Limited | Financial services | 2025 |
| Holligo Lodge Residents RTM Company Limited | Households | 2019 |
| Hollingdean Performing Arts CIC | Education | 2023 |
| Hollings Holdings Limited | Agriculture & fishing | 1980 |
| Hollyland Limited | Real estate | 2017 |
| Hollywood 2 Limited | Real estate | 2025 |
| Hollywood Woking Ltd | Real estate | 2023 |
| Holt Legal Limited | Professional & scientific | 2021 |
| Holt Publishing Limited | Administrative & support | 2015 |
| Holy Streams Ltd | Real estate | 2025 |
| Home Actually Limited | Manufacturing | 2023 |
| Home Appliances South East Limited | Other services | 2026 |
| Home Concepts P&D Limited | Construction | 2025 |
| Home Creators Holdings Limited | Financial services | 2019 |
| Home Farm Solar 1 Limited | Energy | 2014 |
| Home James Residential Limited | Real estate | 2015 |
| Home Project Limited | Real estate | 2010 |
| Home Service Sussex and Kent Limited | Other services | 2024 |
| Home Services Leeds Ltd | Professional & scientific | 2025 |
| Home Support (MK) Limited | Administrative & support | 2011 |
| Home Yatirim Ltd | Real estate | 2023 |
| Home-Tech Support Limited | Manufacturing | 2015 |
| Homeassurety Ltd | Other services | 2022 |
| Homefront Property Group Ltd | Households | 2025 |
| Homehunters France Limited | Real estate | 2003 |
| Homely & Co. (UK) Ltd | Construction | 2025 |
| Homemade Management Limited | Real estate | 2013 |
| Homes App Ltd | Information & communication | 2023 |
| Homes for the City of Brighton & Hove LLP | | 2017 |
| Homeshield Direct Ltd | Other services | 2016 |
| Hometruth Ltd | Information & communication | 2025 |
| Honey Cake by Mary Ltd | Wholesale & retail | 2026 |
| Honeybee Eastbourne Ltd | Wholesale & retail | 2019 |
| Honeycroft | Education | 2002 |
| Honeyman Properties Limited | Real estate | 1986 |
| Honeysome Road Solar Limited | Energy | 2015 |
| Hongkonger in Brighton CIC | Hospitality | 2022 |
| Hoodoo FX Limited | Information & communication | 2012 |
| Hoonsarang Limited | Hospitality | 2024 |
| Hooper Grey Properties Limited | Construction | 2006 |
| Hooray Health & Protection Limited | Extraterritorial | 2019 |
| Hooton Developments Limited | Professional & scientific | 1983 |
| HOP Consulting Limited | Professional & scientific | 2002 |
| Horizon IT Limited | Information & communication | 2011 |
| Horsham Installations Ltd | Construction | 2013 |
| Horus Dental Supplies Ltd | Health & social care | 2018 |
| Horus EGY Ltd | Transport & logistics | 2017 |
| Hosiden Besson Limited | Manufacturing | 1989 |
| Hospitality Inns Sussex Ltd | Hospitality | 2026 |
| Hot Buffer Limited | Information & communication | 2026 |