| London Property Sourcing Ltd | Real estate | 2023 |
| London Residential Developments Limited | Construction | 2018 |
| London Testing & Maintenance Ltd | Manufacturing | 2010 |
| LONGPRIME2 Ltd | Real estate | 2016 |
| Loughton Care Centre Limited | Health & social care | 2011 |
| Louis IS NOT Limited | Real estate | 2024 |
| Lovewildorganics Ltd | Extraterritorial | 2014 |
| Loyallty Limited | Information & communication | 2025 |
| Lrhe Investments Company Limited | Real estate | 2022 |
| Lrhe Property Limited | Real estate | 2025 |
| Lsdh Ltd | Hospitality | 2021 |
| LSS Walthamstow Limited | Arts & recreation | 2015 |
| Lucian Engineering Limited | Construction | 2023 |
| Lucioli Catering Services Ltd | Wholesale & retail | 2025 |
| Lucky Property London LLP | | 2025 |
| Lucra Partners Ltd | Information & communication | 2025 |
| Lugenco Ltd | Other services | 2021 |
| Luka Portfolio Homes Ltd | Real estate | 2025 |
| Lument Ltd | Arts & recreation | 2018 |
| Lumos Academy Limited | Education | 2024 |
| Luxing Limited | Wholesale & retail | 2023 |
| Luxury Interiors & Construction Ltd | Construction | 2026 |
| Luxury Property 13 Ltd | Real estate | 2025 |
| Luxx Stairwell Chandeliers Ltd | Construction | 2025 |
| M & R Duke Investments Limited | Real estate | 2004 |
| M B Tech Projects Limited | Professional & scientific | 2022 |
| M&A Edulex Ltd | Real estate | 2012 |
| M&M&M Limited | Professional & scientific | 2020 |
| M&T Petrovi 17 Ltd | Construction | 2023 |
| M.A.R.M. (Freeholders) Limited | Real estate | 2022 |
| M.A.R.M. Limited | Households | 1989 |
| M.K & Bros Home Hardware Ltd | Wholesale & retail | 2024 |
| MA Umana Ltd | Professional & scientific | 2023 |
| Maas Ventures Limited | Real estate | 2023 |
| Macari Construction Ltd | Construction | 2026 |
| Madana Contracts Ltd | Construction | 2023 |
| MAG Building Ltd | Construction | 2023 |
| MAG Innovations Ltd | Professional & scientific | 2015 |
| Mahindra Limited | Professional & scientific | 2020 |
| Maid in Chigwell Ltd | Administrative & support | 2022 |
| Maidah Arts and Crafts Limited | Wholesale & retail | 2017 |
| Maier Enterprises Ltd | Real estate | 2022 |
| Mairaj Holdings Limited | Wholesale & retail | 2023 |
| MAK Blue.. Ltd | Wholesale & retail | 2021 |
| Mallubrunch Ltd | Hospitality | 2026 |
| Manage My Properties Limited | Other services | 2022 |
| Mandan Investments Limited | Construction | 1982 |
| Mandelbaum Disley Limited | Real estate | 2026 |
| Manford Fish and Grill Ltd | Hospitality | 2023 |
| Manford Traders Ltd | Wholesale & retail | 2023 |
| Manford Way Ltd | Hospitality | 2022 |
| Mannamead Care Centre Limited | Health & social care | 2009 |
| Manor Road Store Ltd | Wholesale & retail | 2020 |
| Manor Spice Ltd | Hospitality | 2024 |
| Mantraraj Properties Ltd | Real estate | 2025 |
| Maple Leafs Home Appliances Ltd | Wholesale & retail | 2026 |
| Marca Sports Limited | Professional & scientific | 2022 |
| Marcantonio Rentals Limited | Real estate | 2026 |
| Margherita Pizzeria Ltd | Hospitality | 2026 |
| Marigold Delta Limited | Other services | 2025 |
| Mariyan Cosmetics Ltd | Wholesale & retail | 2024 |
| Marker Air Ltd | Transport & logistics | 2024 |
| Marku Property Investments Ltd | Real estate | 2018 |
| Mars Promoters Limited | Financial services | 2022 |
| Marty Ltd | Transport & logistics | 2020 |
| Maryam Fire Safety Ltd | Public administration | 2012 |
| MAS Assets Ltd | Real estate | 2022 |
| MAS Construction London Ltd | Construction | 2024 |
| MAS Consular & Legalisation Ltd | Administrative & support | 2021 |
| MAS Properties Development Ltd | Real estate | 2023 |
| Matharu Properties Limited | Real estate | 2017 |
| Mawaddah Holdings Ltd | Education | 2025 |
| Maxim's Building Solutions Ltd | Construction | 2020 |
| MAY Anderson Limited | Professional & scientific | 2021 |
| Maytech Limited | Information & communication | 1997 |
| MBP Delivery Ltd | Transport & logistics | 2022 |
| Mburney Autos Ltd | Wholesale & retail | 2025 |
| Mckirans Limited | Real estate | 1979 |
| MCL Cleaning Limited | Administrative & support | 2025 |
| MCV Full Construction Ltd | Construction | 2023 |
| MD Greaves Limited | Construction | 2021 |
| MD. Unique Ltd | Manufacturing | 2019 |
| MEA Property Group Limited | Real estate | 2019 |
| Medcon Care Ltd | Health & social care | 2016 |
| Medics Personnel Ltd | Administrative & support | 2019 |
| Mediera Limited | Other services | 2025 |
| Medina Goods & Decor Ltd | Wholesale & retail | 2026 |
| Medivisit Ltd | Health & social care | 2023 |
| Megna Business Solutions Ltd | Administrative & support | 2022 |
| Mekomi Ltd | Wholesale & retail | 2016 |
| Mentally Move Limited | Health & social care | 2019 |
| Merccimac Ltd | Administrative & support | 2023 |
| Mercielle Diamonds Hatton Garden Ltd | Wholesale & retail | 2024 |
| Mercurial Developments Ltd | Real estate | 2019 |
| Metropolitan Police Chigwell Sports Club Limited | Arts & recreation | 2008 |
| MGB Construction Services Ltd | Construction | 2020 |
| MGB Contractors Ltd | Construction | 2008 |
| MGB Group Holdings Ltd | Financial services | 2020 |
| MGB Plant Ltd | Construction | 2020 |
| MGB Structures Ltd | Construction | 2020 |