| Hoyles Meadow (Cottam) Residents Management Company Limited | Households | 2021 |
| Human Element Productions Ltd | Information & communication | 2018 |
| Hunter Treehouses Ltd | Agriculture & fishing | 2017 |
| Huntingwood Developments Ltd | Real estate | 2008 |
| Huntingwood Holdings Ltd | Financial services | 2024 |
| Huntsman Cars Ltd | Wholesale & retail | 2023 |
| Hydro Environmental Consultancy Limited | Professional & scientific | 2007 |
| Hyperformance Limited | Financial services | 1999 |
| Ianic Ltd | Other services | 2021 |
| Iccl Ltd | Hospitality | 2009 |
| IKO & Partners Limited | Information & communication | 2023 |
| Ilmits Ltd | Information & communication | 2017 |
| Images Ltd | Arts & recreation | 2024 |
| Impact Training & Consultancy Solutions Ltd | Education | 2024 |
| Impala Visions Limited | Information & communication | 2015 |
| Imperial Gardens (Howden) Management Company Limited | Households | 2019 |
| IN Car Limited | Extraterritorial | 2002 |
| Incabrook Limited | Hospitality | 1996 |
| Incremental Change Limited | Information & communication | 2015 |
| Indivala Tarporley Ltd | Hospitality | 2025 |
| Indubitable Management Limited | Professional & scientific | 2016 |
| Inglewood Manor Limited | Hospitality | 2003 |
| Inpro Architectural Products Ltd | Professional & scientific | 2020 |
| Inspire Solutions Ltd | Professional & scientific | 2023 |
| Instinct Wellness Limited | Health & social care | 2014 |
| Intellect Investments Ltd | Administrative & support | 2013 |
| Intemporel Creative Ltd | Professional & scientific | 2025 |
| International Bankruptcy Searches Limited | Information & communication | 2021 |
| Iris Residents Management Company Limited | Households | 2024 |
| Isaacs Farm Limited | Other services | 2017 |
| Isleport Grove Residents Management Company Limited | Households | 2023 |
| Ispalmer Ltd | Professional & scientific | 2023 |
| Ithaca Designs Limited | Real estate | 1999 |
| J & L Auto Techniks Ltd | Manufacturing | 2015 |
| J B Williams Limited | Extraterritorial | 2007 |
| J John Anaesthetic Services Ltd | Health & social care | 2019 |
| J L Symms Property Limited | Real estate | 2023 |
| J R Drinkall (Livestock) Limited | Agriculture & fishing | 2011 |
| Jack Fabby Racing Limited | Arts & recreation | 2020 |
| Jacqueline Wilson Independent Funeral Services Limited | Other services | 2012 |
| James Allen Electrical Services Limited | Professional & scientific | 2012 |
| James Allen Property Services Limited | Real estate | 2018 |
| James Paige Marketing Limited | Professional & scientific | 2004 |
| James Scott Joinery & Sons Limited | Construction | 2014 |
| James Winter Sport Horses Limited | Agriculture & fishing | 2019 |
| Jasmine Fields Management Company Limited | Households | 2026 |
| JD Latham Ltd | Wholesale & retail | 2011 |
| JEC Tree Services Ltd | Administrative & support | 2023 |
| Jellicoe Gardens (Moreton) Residents Management Company Limited | Households | 2021 |
| JF Fencing and Tree Services Ltd | Agriculture & fishing | 2022 |
| Jfdi Trading Ltd | Wholesale & retail | 2020 |
| JFH Consultancy Ltd | Professional & scientific | 2022 |
| Jfpf Limited | Professional & scientific | 2019 |
| JI Dining Ltd | Hospitality | 2019 |
| Jigsaw Enterprise Services Limited | Professional & scientific | 2025 |
| JIM Crosbie Consulting Limited | Professional & scientific | 2025 |
| JK Yates Ltd | Professional & scientific | 2018 |
| JL Security (NW) Ltd | Construction | 2018 |
| Jmcd Exec Coach Limited | Professional & scientific | 2024 |
| Jmcrecoverys Ltd | Wholesale & retail | 2023 |
| Joe.W Haulage Ltd | Transport & logistics | 2025 |
| Johnson Building Contractors Limited | Construction | 2012 |
| Joshie Limited | Extraterritorial | 2010 |
| Joshua Limited | Extraterritorial | 2017 |
| JPO Lettings Limited | Hospitality | 2023 |
| JR Management Ltd | Professional & scientific | 2015 |
| JV Prop Services Ltd | Information & communication | 2022 |
| JW & CH Health Ltd | Financial services | 2024 |
| K George's Vale (Cuffley) Management Company Limited | Households | 2023 |
| K. R. Exhibition Services Limited | Professional & scientific | 2003 |
| K.Richard’S Wharf Management Company Ltd | Households | 2022 |
| KBS Corporate Services Ltd | Administrative & support | 2010 |
| KDI Applications Limited | Information & communication | 2006 |
| Kelsall Hill Limited | Administrative & support | 2004 |
| Kelsallcycles Ltd | Wholesale & retail | 2020 |
| Key Bidco Limited | Financial services | 2011 |
| Key Claims and Administration Services Limited | Financial services | 2016 |
| Key Midco Limited | Financial services | 2011 |
| Key Topco Limited | Financial services | 2011 |
| Kigi Consulting Ltd | Professional & scientific | 2015 |
| Kingdom Stays Ltd | Real estate | 2026 |
| Kingsley Manor Management Company Limited | Households | 2022 |
| Kinsey Farming Limited | Extraterritorial | 1996 |
| Kirby Cattle Services Limited | Agriculture & fishing | 2020 |
| Kisho LLP | | 2019 |
| KJT Procurement Limited | Professional & scientific | 2007 |
| Klickit Digital Ltd | Information & communication | 2017 |
| Knightwood Chase (Fordingbridge) Residents Management Company Limited | Households | 2025 |
| Komodita Ltd | Professional & scientific | 2014 |
| KR Events Group Limited | Other services | 2025 |
| L C Maguire Property Investments Limited | Real estate | 2025 |
| L.P Art Group Ltd | Arts & recreation | 2017 |
| L.P. Griffiths Limited | Administrative & support | 1995 |
| LA Casina Ltd | Real estate | 2026 |
| Lake Side Events Limited | Hospitality | 2020 |
| Lakefield Business Services Limited | Financial services | 2017 |
| Lamprey Road Court (Apartments) Resident Management Company Limited | Households | 2020 |
| Lancaster Fold Boroughbridge Management Company Limited | Households | 2026 |
| Landmarkex Limited | Real estate | 2020 |
| Latham Farming Limited | Agriculture & fishing | 2015 |