| HSS Industrial Limited | Administrative & support | 2025 |
| Hss-Online Limited | Extraterritorial | 2013 |
| Hssl Developments Limited | Real estate | 2024 |
| HT Care Limited | Health & social care | 2015 |
| HT Care Rental Ltd | Real estate | 2022 |
| HU11 Ltd | Water & waste | 2026 |
| Hudsons Removals Ltd | Transport & logistics | 2007 |
| Hughes Property Solutions Limited | Real estate | 2025 |
| Hull Seahawks Limited | Arts & recreation | 2022 |
| Hulse Consultants Ltd | Professional & scientific | 2025 |
| Human Alchemy KM Ltd | Information & communication | 2024 |
| Human Capital Club Limited | Manufacturing | 2015 |
| Hundred Oaks Ltd | Hospitality | 2025 |
| Hungry Buddha Street Food Ltd | Hospitality | 2025 |
| Hunkins J Limited | Wholesale & retail | 2023 |
| Hunting Systems Ltd | Information & communication | 2013 |
| Hurst Setter & Associates Limited | Other services | 1992 |
| HUS Customs Ltd | Wholesale & retail | 2020 |
| Husky Plumbing and Heating Ltd | Construction | 2023 |
| Hussain Quantity Surveyors Ltd | Professional & scientific | 2021 |
| Hussainroth Ltd | Hospitality | 2025 |
| Hussein Lettings Ltd | Real estate | 2025 |
| Hutcats Clothing Limited | Wholesale & retail | 2025 |
| Hutchinson Court Residents' Association Limited | Households | 1981 |
| Hutchinsons Travel Ltd | Transport & logistics | 2019 |
| Huto Limited | Real estate | 2017 |
| HUX Press Ltd | Wholesale & retail | 2025 |
| Hybrid Gurus Ltd | Wholesale & retail | 2023 |
| Hycinth Consulting Ltd | Professional & scientific | 2024 |
| Hyde Chadwick Limited | Other services | 2017 |
| Hydetech Recruitment Limited | Construction | 2025 |
| Hydra Global Holdings Ltd | Financial services | 2022 |
| Hydra Park Properties Ltd | Real estate | 1988 |
| Hydramatic Source & Supply Ltd | Manufacturing | 2000 |
| Hydraulic Pumps (UK) Limited | Manufacturing | 1987 |
| Hydroculture CIC | Agriculture & fishing | 2025 |
| Hydropower Bathrooms & Heating Ltd | Wholesale & retail | 2025 |
| Hydrostorm Ltd | Wholesale & retail | 2026 |
| Hygenix Ltd | Administrative & support | 2015 |
| Hygge Life CIC | Education | 2024 |
| Hyland Services Group Limited | Administrative & support | 2025 |
| HYLAND2000 Limited | Wholesale & retail | 2024 |
| HYPERION13 Ltd | Information & communication | 2023 |
| Hypersloth Ltd | Information & communication | 2013 |
| HZ Spice Limited | Hospitality | 2025 |
| I C Gears Limited | Manufacturing | 2016 |
| I DO Fancy Ltd | Wholesale & retail | 2018 |
| I Wood Furniture Ltd | Wholesale & retail | 2007 |
| I&A Coatings Ltd | Manufacturing | 2022 |
| I-Trek Logistics Limited | Transport & logistics | 2016 |
| I-Vevane Healthcare Ltd | Health & social care | 2013 |
| I-Wax Ltd | Other services | 2019 |
| I.A.M Your Solutions Ltd | Health & social care | 2019 |
| I.E.D Building Services Ltd | Construction | 2019 |
| I.M. Rail Ltd | Construction | 2017 |
| IA Ophthalmic Limited | Health & social care | 2011 |
| IAN Collins Enterprises Ltd | Professional & scientific | 2015 |
| IAN Hayden Ltd | Construction | 2018 |
| IAN Marsh Electrical Limited | Construction | 2003 |
| Iaso Consulting Group Ltd | Professional & scientific | 2023 |
| IB Partners - Management and Advisory Ltd | Information & communication | 2021 |
| Ibbeson & Sons Investments Ltd | Financial services | 2024 |
| Ibbeson Commercial & Land Ltd | Real estate | 2025 |
| Ibbeson Properties Limited | Real estate | 2019 |
| Ibex Automotive Limited | Wholesale & retail | 2018 |
| Ibhooks Ltd | Wholesale & retail | 2020 |
| Ibii Retails Ltd | Wholesale & retail | 2026 |
| Ibrowse Furniture Limited | Wholesale & retail | 2014 |
| IC 102 Limited | Financial services | 2012 |
| Iccounting Ltd | Professional & scientific | 2020 |
| ICD Energy Metering Services Limited | Construction | 2019 |
| ICD Energy Training Academy Ltd | Energy | 2017 |
| ICD Energy Utilities Ltd | Construction | 2019 |
| Ice N Easy Limited | Hospitality | 2006 |
| Iceotope Group Limited | Manufacturing | 2013 |
| Iceotope Technologies Limited | Manufacturing | 2012 |
| Iconic Glow Limited | Other services | 2023 |
| ID YOU Ltd | Wholesale & retail | 2024 |
| Idea ST Ltd | Administrative & support | 2019 |
| Idea UK Design and Marketing Ltd | Professional & scientific | 2009 |
| Ideal Brokers Limited | Financial services | 2022 |
| Ideal Home Improvements Limited | Manufacturing | 2022 |
| Ideal Properties Investment Ltd | Real estate | 2024 |
| Ideation Brands Limited | Professional & scientific | 2014 |
| Ideel Building Services Ltd | Construction | 2022 |
| Idleroad Limited | Information & communication | 2004 |
| Idmac Engineering Limited | Manufacturing | 1989 |
| Idrees Ecom Ltd | Wholesale & retail | 2025 |
| Idris Pharma Ltd | Wholesale & retail | 2018 |
| Idrive: Request a Ride Limited | Extraterritorial | 2024 |
| Ifight Ltd | Information & communication | 2015 |
| Ifra Mumtaz Ltd | Wholesale & retail | 2023 |
| IFS Risk Solutions Ltd | Financial services | 2016 |
| IG Residential Property Ltd | Real estate | 2022 |
| Igloo Signs Ltd | Manufacturing | 2007 |
| Igsustain Limited | Professional & scientific | 2020 |
| IGW Engineering Ltd | Construction | 2022 |
| Iidea Limited | Manufacturing | 2010 |
| Ijuk Ltd | Wholesale & retail | 2022 |
| Ijump Trampoline Parks Limited | Arts & recreation | 2016 |