| Hookham UK Limited | Real estate | 2022 |
| Hoopertek Limited | Information & communication | 2009 |
| Hopson Haulage Ltd | Transport & logistics | 2023 |
| Hortus Holdings Limited | Financial services | 2013 |
| Hortus Holdings Residential Limited | Real estate | 2017 |
| Hoskins SPV Ltd | Construction | 2025 |
| Hotel ST Ives Limited | Hospitality | 2012 |
| House of Hussey Ltd | Professional & scientific | 2022 |
| House of Organics Limited | Wholesale & retail | 2017 |
| House Therapy Limited | Financial services | 2007 |
| Howwill Limited | Construction | 2023 |
| HR Core Solutions Ltd | Administrative & support | 2025 |
| HSS Logistics Ltd | Transport & logistics | 2022 |
| Hueme Ltd | Information & communication | 2025 |
| Huntingdon Dental Laboratory Limited | Health & social care | 2013 |
| Huntingdon Indoor Bowls Club Ltd | Arts & recreation | 1982 |
| Huntingdon Performance Tyres Limited | Wholesale & retail | 2006 |
| Hunts County Sports Ltd | Manufacturing | 2016 |
| Hunts Properties (2000) Ltd | Hospitality | 2016 |
| Hunts Properties Limited | Real estate | 2000 |
| Hyperion Finance Limited | Financial services | 2014 |
| I Jawaid Properties Limited | Real estate | 2020 |
| I Love My Town Limited | Information & communication | 2013 |
| I-Konn Limited | Information & communication | 2013 |
| I.A.R Engineering Ltd | Construction | 2014 |
| I.Auto Detailng (Norfolk) Limited | Administrative & support | 2025 |
| IAN Sells Ltd | Manufacturing | 2014 |
| IB Medical Consultants Limited | Professional & scientific | 2012 |
| Iconic Cleaning Cambridge Limited | Administrative & support | 2023 |
| Iconic Health and Beauty Ltd. | Other services | 2015 |
| ICW Group Limited | Manufacturing | 2023 |
| Identified Developments (Cambridge) Limited | Construction | 2013 |
| Identified Developments ELY Limited | Construction | 2015 |
| Identified Investments Limited | Real estate | 2010 |
| IGF Investments Limited | Real estate | 2024 |
| Ignite Vehicle Services Ltd | Manufacturing | 2022 |
| Ilford Laundry Services Limited | Other services | 2024 |
| Illogan Stores Limited | Wholesale & retail | 2015 |
| Ilux Limited | Information & communication | 2008 |
| Immor Limited | Professional & scientific | 2017 |
| Incarcerated Band Ltd | Information & communication | 2025 |
| Incline Property Limited | Real estate | 2026 |
| Infraconnex Ltd | Construction | 2021 |
| Inkmaker UK Limited | Manufacturing | 2019 |
| Innovation Parking Solutions Limited | Administrative & support | 2010 |
| Innovative Technology Projects Limited | Wholesale & retail | 2000 |
| Inowco Ltd | Professional & scientific | 2024 |
| Inpinnacle Limited | Information & communication | 2019 |
| Inso Ltd | Extraterritorial | 2018 |
| Instamark Limited | Administrative & support | 2014 |
| Integro Doors Ltd | Construction | 2025 |
| Intelligent Installations Limited | Energy | 2016 |
| International Direct Packaging Limited | Manufacturing | 2010 |
| International Exhibitions Group Limited | Manufacturing | 2019 |
| International Mineral Resources Ltd | Mining & quarrying | 2018 |
| Intracel Limited | Professional & scientific | 1986 |
| Invigilo Limited | Mining & quarrying | 2016 |
| Iris MAY Properties Limited | Real estate | 2026 |
| Ironsee Ltd | Information & communication | 2017 |
| Irthlingborough Food Bar Ltd | Hospitality | 2024 |
| Iskate Holdings Limited | Manufacturing | 2019 |
| Iskate Limited | Wholesale & retail | 2019 |
| Isona Limited | Information & communication | 2005 |
| ITP Group Limited | Financial services | 2022 |
| ITP Property Limited | Real estate | 2022 |
| Ivan Spinal Surgery Holdings Limited | Financial services | 2025 |
| Ives HK Limited | Hospitality | 2024 |
| IVO Developments Limited | Construction | 2025 |
| Izel Designs Ltd | Wholesale & retail | 2025 |
| J B Educational Consultancy Limited | Education | 2016 |
| J&K Handicrafts Ltd | Hospitality | 2023 |
| J&R Fowler Investments Limited | Real estate | 2013 |
| J.C.Pomfret Motors Ltd | Wholesale & retail | 2011 |
| J.K.D. Construction Ltd. | Construction | 2006 |
| Jackson Advisory Services Ltd | Professional & scientific | 2024 |
| Jackson Electrical Contractors Ltd | Administrative & support | 2010 |
| Jade Hester Estate Agents Limited | Real estate | 2025 |
| Jadeline Limited | Manufacturing | 2012 |
| Jamie Parker Plumbing,Heating & GAS Services Limited | Administrative & support | 2008 |
| JAN POD Services Ltd | Transport & logistics | 2019 |
| January Capital Ltd | Professional & scientific | 2024 |
| Japan KOI Import Ltd | Agriculture & fishing | 2015 |
| Jarc Investments Limited | Real estate | 2024 |
| JB Business Group Limited | Professional & scientific | 2024 |
| JCD Distribution Ltd | Wholesale & retail | 2024 |
| JD Music Ltd | Administrative & support | 2011 |
| Jefferies Consulting Limited | Professional & scientific | 2019 |
| Jeflack Limited | Households | 2012 |
| JEJ Ltd | Real estate | 2016 |
| JES Consulting Limited | Professional & scientific | 2011 |
| JGS Builders Limited | Construction | 2003 |
| JGS Contractors Limited | Construction | 2015 |
| Jgstocks Ltd | Wholesale & retail | 2024 |
| JH Rentals Ltd | Real estate | 2020 |
| JHD Hospitality Limited | Hospitality | 2017 |
| JI Recruitment Limited | Administrative & support | 2024 |
| Jj's Motorcycle Training Limited | Education | 2014 |
| JL Connor Transport Ltd | Transport & logistics | 2018 |
| JMC Cambridge Limited | Financial services | 2012 |
| Joanna Nails and Spa Ltd | Other services | 2021 |