| Healing Hands by Payal Ltd | Other services | 2026 |
| Health and Independence Care Ltd | Health & social care | 2026 |
| Heath Foods Ltd | Hospitality | 2025 |
| Heath Mews Management Limited | Real estate | 2017 |
| Heath Supermarket Limited | Wholesale & retail | 2017 |
| Heath Villas Ltd | Real estate | 2025 |
| Heathley Property Services Ltd | Construction | 2015 |
| Heathrow Express Parking Ltd | Transport & logistics | 2019 |
| Hebashaurebeth Limited | Health & social care | 2024 |
| HEC Solar UK Ltd | Construction | 2024 |
| Heliconia Limited | Wholesale & retail | 2026 |
| Heliconia Recyclers Limited | Wholesale & retail | 2023 |
| Hello Builder Ltd | Construction | 2014 |
| Henry & Henry Holdings Ltd | Real estate | 2021 |
| Henry Smith Agency Ltd | Other services | 2018 |
| HER Aura Limited | Wholesale & retail | 2025 |
| Herbal London Ltd | Wholesale & retail | 2025 |
| Herhtech Limited | Information & communication | 2025 |
| Heritage Chagos Non-Profit Organisation Limited | Education | 2018 |
| Heritage Entertainment Ltd | Health & social care | 2015 |
| Heritage Lettings and Maintenance Solutions Limited | Real estate | 2026 |
| Herty Enterprise Limited | Wholesale & retail | 2021 |
| Hetu Care Limited | Health & social care | 2014 |
| HFV Electrical Ltd | Construction | 2019 |
| HHB Builders Ltd | Construction | 2019 |
| High Street Nails Ltd | Other services | 2023 |
| Hill & Stan Ltd | Construction | 2025 |
| Hilliner Limited | Wholesale & retail | 2022 |
| Hillview Residences Ltd | Real estate | 2023 |
| Hipact Ltd | Real estate | 2020 |
| Hive-Rd LLP | | 2014 |
| HJ Security Solutions Limited | Administrative & support | 2025 |
| HK Construction Services Ltd | Construction | 2025 |
| HK Market Ltd | Wholesale & retail | 2023 |
| HKR Tech Ltd | Wholesale & retail | 2019 |
| HM Structures Ltd | Professional & scientific | 2021 |
| Hmapropertypursuit Limited | Real estate | 2020 |
| Hmkcreativedesign Ltd | Wholesale & retail | 2025 |
| HMP Cleaning & Refurbish Ltd | Construction | 2023 |
| Holandashop Limited | Wholesale & retail | 2025 |
| Hold IT Down Community Interest Company | Education | 2022 |
| Holistic Support Services Ltd | Public administration | 2018 |
| Hollybank Manor Limited | Extraterritorial | 2007 |
| Home & Kitchen Solutions Ltd | Construction | 2018 |
| Home Love & Keys Ltd | Households | 2020 |
| Homes Art Limited | Construction | 2017 |
| Hope Brothers Limited | Wholesale & retail | 2021 |
| Hope Brothers Shirley Limited | Wholesale & retail | 2022 |
| Hora Traders Ltd | Construction | 2024 |
| Horsford Creative Limited | Professional & scientific | 2026 |
| Hospen Limited | Administrative & support | 2016 |
| Hospital-To-Home Support Services Limited | Health & social care | 2026 |
| Hozo Construction Limited | Construction | 2025 |
| HR Design and Development Ltd | Construction | 2024 |
| HRA Spice Ltd | Hospitality | 2018 |
| HRISTO83 Ltd | Administrative & support | 2019 |
| HS Tutoring Ltd | Education | 2026 |
| HS1 Enterprise Ltd | Other services | 2023 |
| HSA Homes and Lettings Ltd | Hospitality | 2026 |
| Hsha Ltd | Real estate | 2023 |
| Hsil Solutions Ltd | Professional & scientific | 2026 |
| HSN Dynasty Limited | Hospitality | 2022 |
| Hudson and Thames Studio Ltd | Wholesale & retail | 2021 |
| Hughes Creative Ltd | Professional & scientific | 2025 |
| Hugo Harrison Limited | Transport & logistics | 2020 |
| Humza Productions Ltd | Information & communication | 2011 |
| Hundre Ltd | Wholesale & retail | 2025 |
| Hungry Mate Ltd | Hospitality | 2021 |
| Hybrid 360 Limited | Information & communication | 2022 |
| Hyperse Limited | Wholesale & retail | 2023 |
| I&A Eproducts Ltd | Wholesale & retail | 2022 |
| I&N Caterers Ltd | Hospitality | 2023 |
| I-L & V Ltd | Manufacturing | 2025 |
| I1ARCHITECTURE Ltd | Professional & scientific | 2024 |
| IAC Services Ltd | Transport & logistics | 2023 |
| IAN Graeme Crook Ltd | Construction | 2025 |
| IAS Telecom Limited | Construction | 2025 |
| Ibbi Mart Ltd | Wholesale & retail | 2024 |
| ICY & Zeeks Ltd | Administrative & support | 2019 |
| Ideal Beauty Limited | Real estate | 2007 |
| IGNITE93 Solution Ltd | Construction | 2024 |
| Ignition Finance Ltd | Financial services | 2025 |
| IH Care Ltd | Health & social care | 2020 |
| Ihor Duda IH Limited | Construction | 2026 |
| Ihsan Niazi Ltd | Wholesale & retail | 2024 |
| IIB Management Ltd | Real estate | 2020 |
| IJ Retail Ltd | Wholesale & retail | 2026 |
| Iknow Heating Ltd | Construction | 2023 |
| IKZ Property Development Ltd | Real estate | 2024 |
| Ilewa Care Group Limited | Health & social care | 2025 |
| Illakiya (North Cheam) Ltd | Hospitality | 2019 |
| Ilogbo-Ekiti Descendants Union UK & Europe Chapter | Other services | 2025 |
| ILS Operations Ltd | Hospitality | 2018 |
| Imagination Movers Limited | Other services | 2012 |
| Impressai Ltd | Manufacturing | 2026 |
| IN Demand Transport Ltd | Transport & logistics | 2025 |
| IN the City Media Ltd | Professional & scientific | 2021 |
| Inami Basra Builders Ltd | Construction | 2025 |
| Indesign (London) Limited | Wholesale & retail | 1984 |
| Indian Event Catering Ltd | Professional & scientific | 2019 |