| Hemp Construction Ltd | Construction | 2021 |
| Hemp Eats Ltd | Wholesale & retail | 2020 |
| Henderson Close Management Limited | Households | 1982 |
| Henley Strategic Consulting Limited | Professional & scientific | 2026 |
| Hermanish Ltd | Professional & scientific | 2015 |
| Hestia Cleaning Specialists Ltd | Administrative & support | 2025 |
| Hickman Dairies Ltd | Wholesale & retail | 2013 |
| Hidden Fairy Ltd | Arts & recreation | 2021 |
| Hidden GEM - Your Virtual PA Limited | Administrative & support | 2017 |
| Hier Tier Estates Limited | Hospitality | 2017 |
| High Resolution Limited | Information & communication | 2014 |
| High Voltage Power Engineering Limited | Construction | 2023 |
| Highgrange Limited | Real estate | 2019 |
| Hilhouse & Coco Limited | Real estate | 2024 |
| Hill House Sport Horses Ltd | Agriculture & fishing | 2017 |
| Hill Street (Trowbridge) Management Company Limited | Households | 2002 |
| Hillcrest (Bath) Management Company Limited | Households | 2017 |
| Hirons Decor Services Ltd | Other services | 2018 |
| Hixxysoft Ltd | Wholesale & retail | 2017 |
| HJH Tooling Ltd | Wholesale & retail | 2014 |
| HM Hairdressing Limited | Other services | 2022 |
| HM Project Partnership Limited | Information & communication | 2024 |
| HM Scicomms Ltd | Professional & scientific | 2025 |
| HMO Specialists Ltd | Professional & scientific | 2019 |
| Hmsc Music Ltd | Arts & recreation | 2025 |
| Hoare Associates Ltd | Arts & recreation | 2015 |
| Hockley Residential Investments Ltd | Real estate | 2025 |
| Holborn Asset Management Limited | Professional & scientific | 2000 |
| Hold the Chaos Ltd | Professional & scientific | 2026 |
| Holistic Alchemy Ltd | Health & social care | 2024 |
| Home Accessory Limited | Real estate | 2025 |
| Home Editing Limited | Administrative & support | 2013 |
| Home Fixer Ltd | Construction | 2026 |
| Home Study Courses Limited | Education | 1998 |
| Honey on the Hill Ltd | Wholesale & retail | 2020 |
| Honeyands Investments Limited | Other services | 2025 |
| Honeybee Nanny Agency Ltd | Administrative & support | 2025 |
| Honour Healthcare Ltd | Administrative & support | 2019 |
| HOP Till YOU Drop Ltd | Arts & recreation | 1999 |
| Hot Sausage Company (Bath) Limited | Hospitality | 2012 |
| Hotwire Studios Limited | Manufacturing | 2013 |
| House Law Limited | Professional & scientific | 2020 |
| House of MAC Hair Ltd | Other services | 2021 |
| House of Sherlock Limited | Wholesale & retail | 2023 |
| HOW WE Roll Ltd | Hospitality | 2025 |
| HP Accountancy Services Limited | Professional & scientific | 2022 |
| Hudds Electrical Services Limited | Construction | 2014 |
| Hudson Property Services (Bath) Ltd | Construction | 2018 |
| Hulkzilla Ltd | Professional & scientific | 2021 |
| Hvpe Holdings Limited | Financial services | 2025 |
| I CAN and I AM Limited | Education | 2015 |
| I Dress Myself Ltd | Manufacturing | 2013 |
| I Enjoy Plus (London) Limited | Administrative & support | 2014 |
| I Hate Running Ltd | Wholesale & retail | 2025 |
| I M Smile Ltd | Health & social care | 2010 |
| I.A. DE Jaeger Limited | Real estate | 1957 |
| IAN J Clark Ltd | Wholesale & retail | 2003 |
| Ibex Environmental Limited | Construction | 1996 |
| Ibex Services Limited | Construction | 1985 |
| Ice Bricklaying Ltd | Construction | 2017 |
| Icfdirect (Southern) Ltd | Wholesale & retail | 2022 |
| Iconnectit Ltd | Information & communication | 2024 |
| Idle + Wonder Events Ltd | Hospitality | 2024 |
| Idle + Wonder Studio Ltd | Professional & scientific | 2021 |
| Ifacilitate Ltd | Professional & scientific | 2016 |
| Igbioscience Limited | Wholesale & retail | 2020 |
| Illumina Ltd | Construction | 2018 |
| Ilminster Warehouse Limited | Wholesale & retail | 2009 |
| Ilsley Ballantyne Ltd | Professional & scientific | 2025 |
| Imolla Commercials Limited | Wholesale & retail | 2022 |
| Impact Commercial Flooring Limited | Construction | 2020 |
| Impact Scaffold Ltd | Construction | 2023 |
| Imperium Garden Rooms Limited | Construction | 2023 |
| Impress Colour Ltd | Manufacturing | 2003 |
| IN Full Flight Limited | Professional & scientific | 2017 |
| In-Flight Entertainment Limited | Information & communication | 2019 |
| Inca Investments Ltd | Real estate | 2022 |
| Incred Consultancy Ltd | Information & communication | 2018 |
| Indian Cuisine Oldford Ltd | Hospitality | 2025 |
| Indulgence Beauty Salon (Trudoxhill) Limited | Other services | 2016 |
| Inference Research LLP | | 2022 |
| Infology Software Limited | Information & communication | 2009 |
| Inlay Management Services Limited | Construction | 2009 |
| Inno Instrument UK Ltd | Wholesale & retail | 2021 |
| INNOV8 Automotive Ltd | Wholesale & retail | 2019 |
| Inspired Joinery Limited | Administrative & support | 2010 |
| Insta Heat South-West Limited | Construction | 2022 |
| Intense Retail Ltd | Professional & scientific | 2013 |
| Intention Logistical Solutions Ltd | Transport & logistics | 2025 |
| Intercode Limited | Information & communication | 2005 |
| Interface Essential Marketing Services Limited | Administrative & support | 2010 |
| International Ballet Intensives Ltd | Arts & recreation | 2024 |
| International Production Network Ltd | Arts & recreation | 2012 |
| Interoperable Solutions Ltd | Wholesale & retail | 1995 |
| Intouch Cafe CIC | Hospitality | 2024 |
| Intrinity Consulting Ltd | Administrative & support | 2010 |
| Iron Lion Gymnasium Ltd | Arts & recreation | 2018 |
| Iron-Age Forge Ltd | Administrative & support | 2003 |
| Ironart Limited | Manufacturing | 1967 |
| Irvin Equine Ltd | Transport & logistics | 2024 |