| Hardy & Hughes Ltd | Construction | 2021 |
| Harofi Limited | Administrative & support | 2023 |
| Harvest Bourne Ltd | Real estate | 2025 |
| Haversine Ltd | Information & communication | 2013 |
| Hawfinch Developments Limited | Construction | 2015 |
| Hazeland Company Secretarial Support Limited | Professional & scientific | 2016 |
| Hazelwood Landscapes Limited | Administrative & support | 2014 |
| Headland Consultants Ltd | Professional & scientific | 2012 |
| HEG Property Maintenance Ltd | Administrative & support | 2017 |
| Helen Wells Interiors Ltd | Wholesale & retail | 2020 |
| Hempkin Holdings Limited | Wholesale & retail | 2024 |
| Henderson Drylining Ltd | Construction | 2022 |
| Heritage Masonry Contracts (HMC) Ltd | Construction | 2015 |
| HFB Financial Planning Limited | Professional & scientific | 2013 |
| High Voltage Power Specialists Ltd | Construction | 2023 |
| Highgrade Nutrition Ltd | Wholesale & retail | 2022 |
| Hills Haulage Services Limited | Transport & logistics | 1988 |
| Hire Warehouse Limited | Administrative & support | 2021 |
| HJA Enterprises Ltd | Wholesale & retail | 2022 |
| Hjsj Properties Limited | Households | 2021 |
| Hlbp Company Ltd | Wholesale & retail | 2020 |
| HMS Billet Limited | Financial services | 2014 |
| Holbeach Property Management Company Limited | Real estate | 2013 |
| Hollow Crown Games Ltd | Information & communication | 2026 |
| Holly Millar Limited | Health & social care | 2023 |
| Holmbrook Interiors Limited | Construction | 2015 |
| Holt House Self Storage Ltd | Transport & logistics | 2020 |
| Homefitz Ltd | Arts & recreation | 2023 |
| Homestead Training Limited | Other services | 2018 |
| House of Geoffro Ltd | Real estate | 2026 |
| HPG Enterprises Ltd | Wholesale & retail | 2021 |
| Hugh Nunn Wholesale Ltd | Wholesale & retail | 2015 |
| Huntingdon Security Group (HSG) Ltd | Administrative & support | 2026 |
| Hybrid Generators Limited | Administrative & support | 2023 |
| IAN Green Plumbing Ltd | Construction | 2024 |
| IAN Peck Building Services Limited | Construction | 2015 |
| IG Agro Limited | Wholesale & retail | 2020 |
| Igloosun Limited | Information & communication | 2005 |
| IL Mulino E&A Limited | Hospitality | 2023 |
| IL Mulino J&E Limited | Hospitality | 2025 |
| Imat 3D ENG Limited | Professional & scientific | 2016 |
| Impressions Management Services Ltd | Construction | 2009 |
| Inception LS Ltd | Professional & scientific | 2011 |
| Indigo Accountancy Limited | Administrative & support | 2008 |
| Infracom Group Ltd | Professional & scientific | 2023 |
| Infusion Electrical Services Ltd | Construction | 2023 |
| Inndemand Ltd | Hospitality | 2023 |
| Inntegral Ltd | Hospitality | 2024 |
| International Rigging Ltd | Information & communication | 2020 |
| Intone Designs Limited | Manufacturing | 1998 |
| Invicta Developments Limited | Construction | 2009 |
| Invicta Gorse Lane Ltd | Construction | 2018 |
| Invictas Engineering (UK) Ltd | Wholesale & retail | 2024 |
| Ishak Limited | Hospitality | 2019 |
| Isite Design Limited | Information & communication | 2005 |
| Izzah Catering Ltd | Hospitality | 2018 |
| J J MAC Farming Ltd | Agriculture & fishing | 2017 |
| J J MAC Ltd | Construction | 2003 |
| J V Bradley Limited | Agriculture & fishing | 2006 |
| J.Etheridge Property Services Ltd | Construction | 2023 |
| J.J.Killeen Ltd | Construction | 2019 |
| JAB Network Solutions Ltd | Other services | 2025 |
| Jackson Financial Services Limited | Administrative & support | 2006 |
| Jakey Limited | Real estate | 2002 |
| James Cottam Flooring Limited | Construction | 2014 |
| James Measures Limited | Agriculture & fishing | 1956 |
| Jandey Limited | Professional & scientific | 2025 |
| Jarteign Housing Associates Ltd | Professional & scientific | 2023 |
| Jason Anthony&Co Ltd | Other services | 2021 |
| Jason Murray Homes Limited | Construction | 2001 |
| JAY JAY UK Limited | Administrative & support | 2000 |
| Jaywren Management Ltd | Financial services | 2024 |
| JBG Solutions Limited | Professional & scientific | 2015 |
| JC System Solutions Limited | Information & communication | 2016 |
| Jenoa Thastrom Ltd | Administrative & support | 2023 |
| Jinny’S Jewellery Limited | Manufacturing | 2018 |
| JL Trading Limited | Wholesale & retail | 2010 |
| Joel Ashton Consultancy & Design Ltd | Administrative & support | 2019 |
| John Furlong Ltd | Real estate | 2024 |
| Jordi Contract Services Limited | Construction | 1998 |
| Jova Global Limited | Wholesale & retail | 2025 |
| JPG & Sons Ltd | Hospitality | 2025 |
| JR Estates Peterborough Ltd | Real estate | 2023 |
| JRH Brickwork Ltd | Construction | 2024 |
| JS Logistic Trans Ltd | Transport & logistics | 2018 |
| JSB Electrical Ltd | Construction | 2020 |
| JTR Works Ltd | Wholesale & retail | 2024 |
| Julian Smith Plumbing & Heating Limited | Construction | 2014 |
| Just What I Need Design Ltd | Wholesale & retail | 2014 |
| JWS Drylining Ltd | Construction | 2026 |
| K & C J Allen Ltd | Wholesale & retail | 2003 |
| K & H Holdings Limited | Professional & scientific | 2019 |
| K D Groundworks Limited | Construction | 2011 |
| K L Dawes Limited | Professional & scientific | 2005 |
| K L S (UK) Ltd | Manufacturing | 1977 |
| K&J Logistics UK Ltd | Transport & logistics | 2022 |
| K2 Communications Limited | Information & communication | 2023 |
| Kalida People Ltd | Professional & scientific | 2015 |
| Kara Trans Limited | Transport & logistics | 2013 |
| Karma Freight Ltd | Transport & logistics | 2014 |