| Instrotec Limited | Construction | 2022 |
| Intensive Interaction Institute Community Interest Company | Education | 2011 |
| Intensive Interaction Limited | Education | 2005 |
| International Magazine Gang Ltd | Information & communication | 2025 |
| Ionut Taxi Ltd | Transport & logistics | 2018 |
| IPS Financial Services Limited | Administrative & support | 1988 |
| Ishalee Ltd | Information & communication | 2026 |
| Ivanhoe Atlantic UK Limited | Professional & scientific | 2012 |
| J Gregory Holdings Ltd | Construction | 2026 |
| J Howard & SON Limited | Construction | 2003 |
| Jack Slade Limited | Professional & scientific | 2023 |
| Jackie Egan Consulting Limited | Professional & scientific | 2011 |
| Jane Bartram Limited | Professional & scientific | 2017 |
| Janine Sohota Limited | Health & social care | 2020 |
| JDS Innovations Ltd. | Wholesale & retail | 2024 |
| Jem&D Ltd | Real estate | 2024 |
| JFJ Trading Limited | Hospitality | 2024 |
| Jigsaw Discovery Partners Limited | Professional & scientific | 2019 |
| JK AR Properties Ltd | Real estate | 2025 |
| JKL Developments Ltd | Construction | 2018 |
| Jmbc Properties Ltd | Real estate | 2014 |
| Jolly Jolie Limited | Professional & scientific | 2013 |
| JRT Property Services Ltd | Construction | 2025 |
| Juricor Law Firm Ltd | Professional & scientific | 2024 |
| Kamparoo Activity Camps Ltd | Education | 2026 |
| Karv Landscapes Limited | Administrative & support | 2011 |
| Kearsley Airways Limited | Manufacturing | 1947 |
| Kiddiesoftplay Ltd. | Administrative & support | 2016 |
| Kinnane Consulting Limited | Professional & scientific | 2012 |
| Knoxby Crane Personnel Ltd | Construction | 2015 |
| Krakhouse Ltd | Real estate | 2024 |
| Krave Station Ltd | Wholesale & retail | 2026 |
| Kudos Credit Management Ltd | Administrative & support | 2022 |
| Kudos Enterprises Ltd | Transport & logistics | 2017 |
| Lams Delight Limited | Hospitality | 2026 |
| Lauren Simpson Creative Ltd | Arts & recreation | 2024 |
| Law Carpentry Ltd | Construction | 2019 |
| LAYERLABS3D Ltd | Manufacturing | 2026 |
| LC Technics Ltd | Manufacturing | 2024 |
| Le-Consulting Limited | Professional & scientific | 2004 |
| Legasea Solutions Ltd | Education | 2021 |
| LGS Windows Limited | Construction | 2022 |
| Limes Garden Limited | Real estate | 2011 |
| Linden House Stansted Ltd | Administrative & support | 2018 |
| Llanos Healthcare Ltd | Health & social care | 2019 |
| Lloyd-Warren Construction Limited | Construction | 2016 |
| London JET Centre (Stanstead) Limited | Transport & logistics | 2014 |
| London JET Charter Limited | Transport & logistics | 2014 |
| Loudar Ltd | Information & communication | 2025 |
| Louies Transport Ltd | Transport & logistics | 2022 |
| Love Rigging Limited | Information & communication | 2012 |
| LPW Plumbing & Heating Limited | Construction | 2020 |
| Lucas Transport Ltd | Transport & logistics | 2024 |
| LVM Properties Limited | Real estate | 2013 |
| LWO Roofing Contracts Ltd | Construction | 2025 |
| M.Caton Associates Limited | Professional & scientific | 2012 |
| Mada Laser and Skin Training Ltd | Other services | 2018 |
| Malcolm Wheeler Ltd | Wholesale & retail | 2014 |
| Mallaghan Communications Ltd | Wholesale & retail | 2017 |
| Mannon Limited | Extraterritorial | 2023 |
| Margo Pizza & Grill Ltd | Hospitality | 2017 |
| Mark C James Ltd | Manufacturing | 2021 |
| Marks TEY Farms Ltd | Construction | 2018 |
| Marsland Engineering Limited | Professional & scientific | 2020 |
| Marsland Enterprises Limited | Construction | 2003 |
| Martins Farm Limited | Mining & quarrying | 2010 |
| Master Lock UK Sales Limited | Wholesale & retail | 2013 |
| MB Elec Consulting Limited | Professional & scientific | 2025 |
| MCA Regulatory Limited | Professional & scientific | 2005 |
| Mckeda Ltd | Real estate | 2017 |
| MCR Accounting Ltd | Administrative & support | 2018 |
| MDL Consultants Ltd | Professional & scientific | 2012 |
| Mead Family Estates Ltd | Real estate | 2026 |
| Medinvest Portal Limited | Administrative & support | 2018 |
| Mi-Sho-Che Ltd | Hospitality | 2025 |
| Milites Ltd | Wholesale & retail | 2025 |
| Miycad Limited | Professional & scientific | 2011 |
| Mizaic Ltd | Information & communication | 2015 |
| MJD Broadcast Ltd | Information & communication | 2020 |
| Mm-Art Consult Ltd | Education | 2021 |
| Moat Agriculture & Transport Ltd | Agriculture & fishing | 2026 |
| Mognolia Consulting Services Ltd | Public administration | 2025 |
| Mole Hill Green Limited | Construction | 2022 |
| Monomindai Ltd | Information & communication | 2025 |
| Mont Place Management Company Limited | Households | 2014 |
| Morleyfile Ltd | Administrative & support | 2024 |
| Morris Wheeler & Co Limited | Professional & scientific | 2008 |
| Mount Pleasant Property Management Ltd | Households | 2022 |
| Mountfitchet Clearance Company Ltd | Water & waste | 2024 |
| Mountfitchet Moving Company Ltd | Transport & logistics | 2021 |
| Mountfitchet Partners Limited | Wholesale & retail | 2022 |
| Mountfitchet Projects Limited | Construction | 2025 |
| Move Logistics Limited | Transport & logistics | 2024 |
| Mvhc Ltd | Professional & scientific | 2013 |
| My Nature Ltd | Other services | 2020 |
| MYT Contracts Limited | Construction | 2012 |
| NELIL87 Ltd | Administrative & support | 2017 |
| Newman's Home Services Limited | Administrative & support | 1987 |
| Nilwaste Compliance Limited | Professional & scientific | 2011 |
| Noel's Property Finder & Management Ltd | Real estate | 2017 |