| Henry Jervis and Partners Ltd. | Construction | 1997 |
| Heritage Accountancy & Taxation Services Limited | Professional & scientific | 2006 |
| Heyford Developments Limited | Real estate | 2004 |
| HMH Consultancy Limited | Professional & scientific | 2025 |
| Hogan's Cider Limited | Manufacturing | 2005 |
| Holdsworth Windows Limited | Manufacturing | 1967 |
| Hollybush Property Developments Limited | Construction | 2000 |
| Honey Blossom Farm Limited | Wholesale & retail | 2003 |
| Horeston Metals Limited | Water & waste | 2003 |
| Horiba Mira Limited | Professional & scientific | 2015 |
| Horizontal and Vertical Ltd | Information & communication | 2002 |
| Hotsprings Limited | Construction | 1963 |
| House of Carpets Limited | Wholesale & retail | 2000 |
| Houseworks Arts Limited | Arts & recreation | 2000 |
| Howards of Stratford Limited | Wholesale & retail | 1990 |
| Howkins and Harrison LLP | | 2005 |
| HT Realisations 2005 Limited | Manufacturing | 1964 |
| Hugo Designs Limited | Other services | 1996 |
| Hurley Hall Farms Limited | Agriculture & fishing | 1962 |
| Hutchison Technical Limited | Information & communication | 2007 |
| Hyde Innovations Limited | Professional & scientific | 1998 |
| Hykleen Limited | Administrative & support | 2006 |
| IAN Neate Limited | Administrative & support | 2007 |
| IC Furniture Limited | Construction | 2010 |
| ICA Technical Solutions Limited | Manufacturing | 2000 |
| Icheme Limited | Information & communication | 1993 |
| Idsl Group Holdings Limited | Financial services | 2024 |
| Ilyn Limited | Professional & scientific | 2005 |
| IMA Swiftpack Limited | Manufacturing | 2004 |
| IMA UK Ltd. | Extraterritorial | 1983 |
| Image + Limited | Information & communication | 1995 |
| Imat Electrical Limited | Professional & scientific | 2006 |
| IN the Wool Shed Limited | Administrative & support | 2015 |
| Indra Foods Limited | Hospitality | 2023 |
| Infotech Solutions (Midlands) Limited | Information & communication | 1997 |
| Inglewood (NO 2) Ltd | Professional & scientific | 1997 |
| Insider and Shop Limited | Manufacturing | 2025 |
| Integrated IT Limited | Information & communication | 1997 |
| Interlotte Management Company Limited | Households | 1981 |
| Invictus Training Solutions Ltd | Education | 2006 |
| Iwillrecordit Limited | Professional & scientific | 2018 |
| J D R Property Limited | Extraterritorial | 2002 |
| J L Bryan Dwcf Limited | Professional & scientific | 2006 |
| J M Care Limited | Health & social care | 2003 |
| J S Trade Limited | Wholesale & retail | 2004 |
| Jackson & Froggatt Limited | Professional & scientific | 1990 |
| Jade Systems Limited | Information & communication | 1996 |
| Jason Gibbs Plumbing & Heating Limited | Construction | 2003 |
| JBC Computer Systems (Coventry) Limited | Information & communication | 2003 |
| JBS Commercial Equipment Limited | Administrative & support | 2004 |
| JBS Commercial Fleet Services Limited | Wholesale & retail | 2003 |
| JBS Commercial Holdings Limited | Financial services | 2004 |
| Jessop Roofing (Midlands) Limited | Construction | 1992 |
| JFC Civils UK Ltd | Manufacturing | 2020 |
| Jigsaw Print Solutions Limited | Manufacturing | 2006 |
| JIM Keeley Associates Ltd | Real estate | 2004 |
| Jinyang Maritime Service Co., Ltd | Administrative & support | 2026 |
| Jivefax Limited | Professional & scientific | 1994 |
| John BYE Images Limited | Arts & recreation | 2006 |
| John Earl Services Limited | Construction | 2005 |
| John Garland-Taylor Limited | Manufacturing | 2017 |
| John H. Cocks & Sons (Farmers) Limited | Agriculture & fishing | 1965 |
| John Lyne Home Improvements Ltd | Wholesale & retail | 2004 |
| Jolt Consultancy Limited | Information & communication | 2011 |
| Jordans Car Repair Services Limited | Wholesale & retail | 2007 |
| Joycom Ltd | Manufacturing | 2002 |
| JP Collins LLP | | 2001 |
| JRB SIX Limited | Professional & scientific | 2007 |
| Just Plain Sense Ltd | Professional & scientific | 2006 |
| Just Properties Developments Limited | Construction | 2005 |
| Jvsv Design Limited | Professional & scientific | 2005 |
| JX Business Limited | Professional & scientific | 2025 |
| K & J Harrison Limited | Professional & scientific | 1966 |
| Kalvi Foundation | Education | 2012 |
| Karo Consulting Limited | Information & communication | 2006 |
| Kaymark Computer Maintenance Limited | Other services | 2000 |
| Keenan Property Development & Construction Limited | Construction | 2005 |
| Kenilworth Golf Club,Limited | Arts & recreation | 1936 |
| Kenilworth Property Developments Limited | Construction | 2006 |
| Kenilworth Property Services Limited | Real estate | 2002 |
| Kenilworth Road Management Leamington Limited | Households | 1981 |
| Kent Plant & Mechanical Engineering Limited | Real estate | 1981 |
| Kilima Associates Ltd | Wholesale & retail | 2003 |
| Kilvington Saville & Partners Limited | Professional & scientific | 1988 |
| Kingfisher Consultancy Limited | Real estate | 1995 |
| Kingfisher Recruitment Specialists Ltd | Administrative & support | 2009 |
| Kirkdale Buildings Limited | Construction | 1999 |
| Kirpa Carers Limited | Health & social care | 2017 |
| KJG Services Ltd | Manufacturing | 2007 |
| Kmack Limited | Construction | 2005 |
| KMH Systems Limited | Professional & scientific | 2013 |
| KNT Trading Limited | Wholesale & retail | 2006 |
| L. Pickering & Sons Limited | Manufacturing | 1950 |
| L.A. Services Limited | Manufacturing | 1984 |
| L.G. Farmer (Engineering) Limited | Manufacturing | 1976 |
| Landlord Furniture Limited | Construction | 2008 |
| Landlord Maintenance Limited | Construction | 2007 |
| Lantanier UK Limited | Financial services | 2012 |
| Lavin Investments Limited | Administrative & support | 2003 |
| Lawson Robb Design Limited | Extraterritorial | 2018 |