| Hayba Healthcare Limited | Health & social care | 2025 |
| Haydari Group Ltd | Real estate | 2018 |
| Hayland Properties (DEV Co) Ltd | Construction | 2020 |
| Hayland Properties Limited | Construction | 1981 |
| Haymaker (Eighteen) Limited | Energy | 2015 |
| Haymaker (Fourteen) Limited | Energy | 2015 |
| Haymaker (Honington Solar) Limited | Energy | 2014 |
| Haymaker (Kinmel) Ltd | Energy | 2014 |
| Haymaker (Nineteen) Limited | Energy | 2015 |
| Haymaker (Seventeen) Limited | Energy | 2015 |
| Haymaker (TEN) Limited | Administrative & support | 2014 |
| Haymaker (Twenty Eight) Limited | Energy | 2022 |
| Haymaker (Twenty Five) Limited | Energy | 2022 |
| Haymaker (Twenty Four) Limited | Energy | 2022 |
| Haymaker (Twenty One) Limited | Energy | 2015 |
| Haymaker (Twenty Seven) Limited | Energy | 2022 |
| Haymaker (Twenty SIX) Limited | Energy | 2022 |
| Haymaker (Twenty Three) Limited | Energy | 2015 |
| Haymaker (Twenty Two) Limited | Energy | 2015 |
| Haymaker (Twenty) Limited | Energy | 2015 |
| Haymaker Energy Limited | Energy | 2013 |
| Hayward Precision GRP Mouldings Ltd | Manufacturing | 2020 |
| Hazell & Partners Ltd | Professional & scientific | 2020 |
| Hazell Forums Ltd | Professional & scientific | 2023 |
| Hazelwood Building Contractors Limited | Construction | 2013 |
| Hazelwood Property Management Ltd | Households | 2019 |
| HB Property Lettings Limited | Real estate | 2023 |
| Hb&Co Ltd | Administrative & support | 2023 |
| Hbrco Limited | Administrative & support | 1996 |
| HC United Limited | Administrative & support | 2026 |
| HCM Accounting Ltd | Professional & scientific | 2023 |
| Health Insurance Matters Ltd. | Financial services | 2004 |
| Health Practice Associates Council CIC | Information & communication | 2017 |
| Healthbuddha Ltd | Wholesale & retail | 2021 |
| Healthcare Revolution Staffing Ltd | Professional & scientific | 2026 |
| Healthspan Festival Ltd | Administrative & support | 2025 |
| Healthwise (Sussex) Ltd | Health & social care | 2016 |
| Healthy Habits for Life Limited | Health & social care | 2007 |
| Healthy Swaps Limited | Wholesale & retail | 2025 |
| Heart and Mind Ltd | Education | 2017 |
| Heart Holistic Massage Limited | Other services | 2017 |
| Heasman Homes Ltd | Households | 2021 |
| Heat Metering Limited | Professional & scientific | 2012 |
| Heat Pump Designer Limited | Professional & scientific | 2025 |
| Heathfield Property Management Limited | Construction | 2014 |
| Heaven in Healthcare | Health & social care | 2020 |
| Hecking Good Ltd | Manufacturing | 2024 |
| Hedley Visick Maintenance Limited | Construction | 2024 |
| Hedy Property Group Ltd | Real estate | 2026 |
| Helio Consultants Ltd | Wholesale & retail | 2026 |
| Helix Carpentry Ltd | Construction | 2026 |
| Helix Medical Recruitment Ltd | Administrative & support | 2018 |
| Helping Hand Property & Maintenance Service Ltd | Construction | 2022 |
| Helybar Limited | Wholesale & retail | 2008 |
| Hemlines & Timelines Limited | Professional & scientific | 2010 |
| Hempstead Patios Limited | Construction | 2024 |
| Henley Exteriors Ltd | Administrative & support | 2019 |
| Hennerz Estates Limited | Real estate | 2009 |
| Henry Brothers Hot Sauce Limited | Hospitality | 2024 |
| Henry Paddon Limited | Wholesale & retail | 2010 |
| Hepburn Homes (the Hobbit) Limited | Construction | 2025 |
| Hepburn Homes Limited | Construction | 2025 |
| HER Bond Ltd | Wholesale & retail | 2025 |
| Herald Court Eastbourne Residents Co. Limited | Households | 2000 |
| Herdplanner Limited | Information & communication | 2026 |
| Heritage Developers Ltd | Construction | 2023 |
| Heritage Parks Limited | Construction | 1992 |
| Heritage Property Limited | Real estate | 2000 |
| Heritage Quay (NO.1) Management Company Limited | Households | 1999 |
| Heritax Group Ltd | Professional & scientific | 2023 |
| Herne Bay Property One Limited | Real estate | 2025 |
| Herne Bay Property Seventeen Limited | Real estate | 2025 |
| Herne Bay Property Three Limited | Real estate | 2025 |
| Herne Bay Property Two Limited | Real estate | 2025 |
| Hero Plumbing Limited | Construction | 2019 |
| Heronswood Consulting Ltd | Administrative & support | 2013 |
| Hesd DM 2 Ltd | Professional & scientific | 2021 |
| Hetherington International Services Limited | Administrative & support | 2020 |
| HEX CS Ltd | Professional & scientific | 2024 |
| HF14 Limited | Real estate | 2013 |
| HFR Property Ltd | Real estate | 2025 |
| HH UK Marketing Ltd | Administrative & support | 2022 |
| HHL Investments Limited | Real estate | 2009 |
| Hi-Line Facilities Ltd | Other services | 2023 |
| Hi-Tec Plant & Building Supplies Limited | Real estate | 1993 |
| Hicam Ltd | Agriculture & fishing | 2014 |
| Hicksoid Limited | Professional & scientific | 2014 |
| Hicrowds Ltd | Manufacturing | 2019 |
| Hidden Identity Productions Limited | Wholesale & retail | 2022 |
| High & Over Limited | Information & communication | 2022 |
| High Class Sussex Ltd | Administrative & support | 2024 |
| High Click Rate Ltd | Professional & scientific | 2017 |
| High Street to YOU Ltd | Transport & logistics | 2025 |
| High Trees (Carew Road) RTM Company Limited | Administrative & support | 2013 |
| High View Maintenance Company Limited | Households | 1974 |
| High-Rd Ltd | Professional & scientific | 2024 |
| Highcombe Residents Association Limited | Households | 1989 |
| Highfield Business Park (Management) Limited | Extraterritorial | 2006 |
| Highgrove Management Company Limited | Households | 2023 |
| Highview Aeronautics Limited | Information & communication | 1999 |