| Hasker Limited | Real estate | 2020 |
| Hastegrove Limited | Households | 1989 |
| Hastings Self Storage Ltd | Real estate | 2011 |
| HAT Retail Ltd | Wholesale & retail | 2022 |
| Hatfield Court (Hove) Limited | Households | 1994 |
| Hatsumi Ltd | Information & communication | 2018 |
| Hatterist Ltd | Professional & scientific | 2020 |
| Haulm Ltd | Public administration | 2020 |
| Haus of Palette Ltd | Wholesale & retail | 2025 |
| Haus Refurbishments Limited | Construction | 2012 |
| Haven Home Improvements Ltd | Construction | 2012 |
| Hawkley Partners Limited | Administrative & support | 2020 |
| Hawkslane Ltd | Real estate | 2022 |
| Hawksley & Sons Limited | Manufacturing | 1980 |
| Hawtex Limited | Households | 2003 |
| HAY Accounting (UK) Ltd | Administrative & support | 2010 |
| Haydon Investment Management Ltd | Financial services | 2013 |
| Hayler Associates Limited | Professional & scientific | 2010 |
| Hayley Isola Limited | Information & communication | 2024 |
| Hayman Partners Ltd | Arts & recreation | 2018 |
| Haynes Legacy Ltd | Real estate | 2025 |
| Haywards Heath Golf Club Limited | Arts & recreation | 1927 |
| Haywards Heath Station Taxis Limited | Transport & logistics | 1956 |
| HBF Dental Limited | Health & social care | 2023 |
| Hbhouse Hove Limited | Other services | 2021 |
| HC Sports and Media Ltd | Arts & recreation | 2025 |
| HCF Psychological Services Ltd | Health & social care | 2015 |
| HD 77 Construction Limited | Construction | 2025 |
| HDP Property Consulting Ltd | Real estate | 2015 |
| HE Developments Ltd | Construction | 2019 |
| HE Property Group Ltd | Financial services | 2020 |
| Head to the Sky CIC | Education | 2022 |
| Headlights on the Parade Ltd | Arts & recreation | 2023 |
| Headline Films Limited | Information & communication | 2014 |
| Heal Awaken Ltd | Health & social care | 2019 |
| Health and Life Sciences Digital Ltd | Information & communication | 2023 |
| Health Rebels Ltd | Wholesale & retail | 2019 |
| Health-Force Limited | Arts & recreation | 2006 |
| Healthcare Network Limited | Financial services | 2012 |
| Healy and Newsom Estate Agents Limited | Real estate | 2014 |
| Healys Property Investments Ltd | Real estate | 2017 |
| Heart and EYE Limited | Arts & recreation | 2024 |
| Heart Pine Ltd | Construction | 2020 |
| Heatfinders Ltd | Construction | 2014 |
| Heath Design Ltd. | Professional & scientific | 2003 |
| Heathen Brewers Limited | Manufacturing | 2016 |
| Heating UP Ltd | Construction | 2019 |
| Heaven Apparel Limited | Wholesale & retail | 2016 |
| Heavenly Bike Fit Limited | Wholesale & retail | 2026 |
| Hedgetv Ltd | Information & communication | 2017 |
| Hedonia Health Limited | Health & social care | 2025 |
| Heidi Joyce Gardens Ltd | Administrative & support | 2022 |
| Heir Student Services Ltd | Hospitality | 2022 |
| Helen Jamieson Health and Wellness Ltd | Health & social care | 2026 |
| Helen Jamieson Ltd | Professional & scientific | 2022 |
| Helen Scott Productions Limited | Information & communication | 2011 |
| Helen's Alterations and Repairs Ltd | Other services | 2024 |
| Helgiford Investments Ltd | Real estate | 2012 |
| Helios Property Management Limited | Real estate | 2013 |
| Hello Enterprises Ltd | Wholesale & retail | 2022 |
| Hells Bells Ltd | Hospitality | 2025 |
| Helmstone Technology Ltd | Information & communication | 2025 |
| Helmwood Ltd | Real estate | 2025 |
| Hendai Solar Limited | Energy | 2013 |
| Hendre Fawr Solar Limited | Energy | 2013 |
| Henfield Homes Decorating Ltd | Construction | 2022 |
| Henhouse Studio Ltd | Wholesale & retail | 2020 |
| Henley Court Management (Brighton) Limited | Households | 1991 |
| Henry Harris Partnership Ltd | Professional & scientific | 2019 |
| Herbs Kingdom TCM Limited | Health & social care | 2018 |
| Hereford House Company Ltd | Households | 2012 |
| Hergoal Ltd | Education | 2024 |
| Heritage Environmental Services Limited | Manufacturing | 2015 |
| Hern International Limited | Information & communication | 2022 |
| Heronlane Limited | Real estate | 1994 |
| Hessenberg Framing Limited | Arts & recreation | 2025 |
| Hesyvolt Limited | Wholesale & retail | 2022 |
| Hevans People Services Ltd | Professional & scientific | 2024 |
| Hexagon Hive Limited | Professional & scientific | 2021 |
| Hexington Ltd | Information & communication | 2019 |
| HEY Girl Magazine Ltd | Information & communication | 2017 |
| Heygate Heating Solutions Ltd | Construction | 2026 |
| HFA Consulting Ltd | Wholesale & retail | 2014 |
| HGR Homes Ltd | Real estate | 2025 |
| HI Dental Limited | Health & social care | 2021 |
| Hi-Sea Limited | Hospitality | 2013 |
| Hi-Tech Computing Limited | Information & communication | 2007 |
| Hiccup (Services) Ltd | Professional & scientific | 2018 |
| Hickmans Legal Costing Services Limited | Professional & scientific | 2000 |
| Hidden Signal Solutions Limited | Information & communication | 2023 |
| Hidden State Games Limited | Information & communication | 2023 |
| Hiddenfield Ltd | Information & communication | 2015 |
| Hiddenmemory Limited | Administrative & support | 2010 |
| Higgins Retail Ltd | Wholesale & retail | 2020 |
| Higginswines Ltd | Hospitality | 2019 |
| High & Mighty Properties Limited | Real estate | 2012 |
| High Class Property Lettings Limited | Real estate | 2024 |
| High Class-Cleaning Ltd | Administrative & support | 2014 |
| High Donut Ltd | Real estate | 2025 |
| High Marketing Ltd | Wholesale & retail | 2025 |