| House of Hope Care Limited | Bangor | 2026 |
| House of Love Care Ltd | Swindon | 2021 |
| House of Sheri CIC | London | 2025 |
| Houzofbrims Limited | Blackburn | 2024 |
| Hove Mindcare Limited | Coalville | 2025 |
| Howards Fire Protection Limited | Newhaven | 2022 |
| Howarth Fire Protection Ltd | Delph | 2021 |
| HP Office Solutions Limited | Barnet | 2013 |
| Hppsir Limited | Chelmsford | 2023 |
| HR 1 Construction Limited | Bootle | 2023 |
| HR Davies Fire Consulting Ltd | Thrapston | 2026 |
| HR Fire & Security Ltd | Retford | 2015 |
| HR Universal Care Limited | Coventry | 2023 |
| HRC Fire Consultancy Ltd | Leeds | 2018 |
| HS86CONSULTING Limited | Kidderminster | 2016 |
| HSE Group Limited | Rochford | 2024 |
| HSE Support and Services (NI) Ltd | Belfast | 2018 |
| Hseq Services Ltd | Newport | 2024 |
| HSM Consultancy Ltd | London | 2026 |
| HST Highview Ltd | Chelmsford | 2021 |
| HSU Fire Alarm Services Ltd | Walsall | 2025 |
| HUA Li's Healthcare Limited | Cardiff | 2022 |
| Hubbard & Clarke Ltd | Hampshire | 2018 |
| Hubey Health Ltd | London | 2026 |
| Human Choice Healthcare Ltd | Hemel Hempstead | 2024 |
| Human Dynamics Group Limited | Acton | 2018 |
| Human Factors Expertise Limited | Sale Moor | 2022 |
| Human Health Education and Research Foundation | Dudley | 2020 |
| Humanitarian and Development Organization (HDO) Ltd | London | 2025 |
| Humber Landlords Association (HLA) | Hessle | 2019 |
| Hummingbird Holistic Therapy Hub C.I.C. | Liverpool | 2025 |
| Humucare&Cleaning Agency Limited | Birmingham | 2022 |
| Hunt Marine Salvage / Firefighting Ltd | Buckhurst Hill | 2026 |
| Hunter Fire Ltd | Nottingham | 2025 |
| Hunter Fire Safety Limited | Romsey | 2022 |
| Hunter Safety Ltd | Sheffield | 2022 |
| Huquqyat Ltd | Fulham | 2021 |
| Huruma Care Services Ltd | Cambridge | 2023 |
| Hussain Medicare Limited | London | 2022 |
| Hussakingham Ltd | Bradford | 2023 |
| HV Healthcare Limited | Bingham | 2014 |
| HW Lifestyle Limited | Croydon | 2019 |
| Hydens (National) Ltd | London | 2024 |
| Hydrants Direct Limited | Wilmslow | 2018 |
| Hydro Fire Protection Services Ltd | Lisnaskea | 2015 |
| Hyfire Limited | Morecambe | 2011 |
| Hyra Health Limited | Dunstable | 2025 |
| Hythe CBT & Emdr Therapy Ltd | Melbourn | 2026 |
| I AM Aware Project C.I.C. | London | 2024 |
| I Believe I CAN Change Ibic Change C.I.C. | London | 2022 |
| I J Pratt Services Limited | Aberdeen | 2011 |
| I-41F Ltd | London | 2025 |
| I-Care Services CIC | Stanmore | 2025 |
| I-Care Support Services Ltd Ltd | London | 2018 |
| I-Cert Electronic Certification Services Limited | Ashford | 2012 |
| I-Mist Ltd | West Malling | 2015 |
| I-Mist Manufacturing Limited | Hull | 2018 |
| I-Mist Products Limited | Hull | 2019 |
| I. S. Fire Safety Ltd | New Romney | 2010 |
| I.D. Fire Stopping Limited | Coventry | 2024 |
| IAN Hopwell Limited | Huntingdon | 2009 |
| IAN Leach Safety Services Limited | Grimsby | 2016 |
| IAN Osborne Limited | Sidcup | 2014 |
| IAP Fire Compliance Ltd | Kidderminster | 2025 |
| IB Fire Protection Ltd | Borehamwood | 2020 |
| IB Fire Safety Consultancy Limited | Lymm | 2025 |
| IB Safety SW Limited | Exeter | 2024 |
| IBC Quality Solutions Limited | Leicester | 2012 |
| Ibrowide Limited | Newtownabbey | 2024 |
| IC Comms Limited | Blackburn | 2008 |
| Ic&C Ltd | Inverness | 2018 |
| Icambridge for Postgraduate and Researches College Ltd | London | 2025 |
| Ican Fire Solution Limited | Ashford | 2023 |
| Icare Happy Ltd | Manchester | 2025 |
| ICARE4HEALTH Ltd | Bristol | 2023 |
| Icon Care Consult Limited | Reading | 2022 |
| ICS Defence Limited | Bungay | 2024 |
| ID Fire Solutions Ltd | Mansfield | 2021 |
| ID Verification Online Ltd | London | 2026 |
| Idakk Ltd | Sheffield | 2022 |
| Ideal Medicare Limited | Aberdeen | 2024 |
| Ideal Social Care Group Ltd | Peterborough | 2023 |
| Idealises Ltd | Bexleyheath | 2025 |
| IDK Ltd | Swindon | 2026 |
| Idlata Services Ltd | Hanwell | 2019 |
| Idsc (Decontamination Science) Ltd | Northampton | 2022 |
| Idylle World Limited | Dagenham | 2024 |
| Ievent Safety Services Ltd | Saffron Walden | 2024 |
| IF YOU ARE Safe I AM Safe | Durham | 2015 |
| IFI Group Ltd | Lincoln | 2017 |
| IFP Systems Ltd | Birmingham | 2019 |
| Ifraim Ltd | Newport | 2024 |
| Iftiin Home Care Ltd | West Drayton | 2022 |
| IG for Education Services Global Ltd | Oxford | 2022 |
| IGC Homecare Ltd | Rugby | 2025 |
| Igni-Uk Limited | Rossendale | 2020 |
| Ignis Compliance Ltd | Pen-Y-Bont Ar Ogwr | 2026 |
| Ignis Fire Limited | Basildon | 2017 |
| Ignis Fire Prevention Ltd | Brentwood | 2020 |
| Ignis Fire Safety Ltd | Dunbartonshire | 2014 |