| LVL UP Network Ltd | Professional & scientific | 2023 |
| LW Kickboxing Ltd | Arts & recreation | 2026 |
| LWFITNESS4ALL Limited | Arts & recreation | 2017 |
| Lwfp Group Ltd | Financial services | 2018 |
| Lxeo Ltd | Administrative & support | 2021 |
| LXR Preloved Ltd | Wholesale & retail | 2022 |
| Lydgate Associates Limited | Information & communication | 2018 |
| Lyfods Ltd | Wholesale & retail | 2023 |
| Lykke Properties Limited | Real estate | 2022 |
| Lyle Close Limited | Households | 2007 |
| Lymph Body Co Ltd | Wholesale & retail | 2026 |
| Lynkr Ltd | Professional & scientific | 2024 |
| Lynsey Alexander Beauty Ltd | Arts & recreation | 2015 |
| Lynvo Ltd | Wholesale & retail | 2025 |
| Lyonsgate Ltd | Wholesale & retail | 2018 |
| Lyonsgate(Uk) Ltd | Professional & scientific | 2013 |
| Lyra Team Ltd | Information & communication | 2025 |
| Lysiun Ltd | Manufacturing | 2023 |
| Lyttle Urology Services Limited | Health & social care | 2025 |
| M & M Leisure Centre (Mildenhall) Limited | Real estate | 1999 |
| M & P Taverns Ltd | Hospitality | 2025 |
| M & R Property Investors Limited | Real estate | 2024 |
| M a Wakeman Electrical Limited | Construction | 2012 |
| M Adam Optical Ltd | Health & social care | 2023 |
| M Bebbington Ltd | Professional & scientific | 2015 |
| M E Hill Oncology Ltd | Health & social care | 2010 |
| M Grace Holdings Ltd | Financial services | 2025 |
| M J Evans Properties Ltd | Real estate | 2025 |
| M J Evans Property Solutions Ltd | Construction | 2025 |
| M J Grab Services Ltd | Administrative & support | 2021 |
| M J Groundworks Ltd | Construction | 2021 |
| M J Money Home Improvements Ltd | Construction | 2023 |
| M K Autos MOT Centre Ltd | Wholesale & retail | 2021 |
| M L Daly Holdings Limited | Financial services | 2016 |
| M L Daly Limited | Professional & scientific | 2016 |
| M P Harris Contracting Ltd | Agriculture & fishing | 2024 |
| M S Welding Limited | Manufacturing | 2014 |
| M Saad Traders Ltd | Wholesale & retail | 2025 |
| M Salman Sarwar Ltd | Wholesale & retail | 2024 |
| M Test Ltd | Professional & scientific | 2018 |
| M W M Batty Holdings Limited | Financial services | 2016 |
| M&K Builds Ltd | Construction | 2025 |
| M&L Aljumely Limited | Real estate | 2023 |
| M&L Professional Services Limited | Professional & scientific | 2023 |
| M&Mcraft Ltd | Manufacturing | 2025 |
| M. and M. Leisure Centre Limited | Real estate | 1976 |
| M. C. Stennett & Sons (Holdings) Limited | Financial services | 1990 |
| M. Louder Property Ltd | Real estate | 2025 |
| M. O. Interactive Limited | Information & communication | 2006 |
| M. Vaiksnys Ltd | Construction | 2007 |
| M. W. Nice Holdings Limited | Financial services | 2024 |
| M.C.L. Transport Limited | Transport & logistics | 1997 |
| M.D. Marine Travel Limited | Administrative & support | 2012 |
| M.Filatovas Ltd | Transport & logistics | 2025 |
| M.Kacevicius Limited | Transport & logistics | 2026 |
| M.Krawczyk Transport Ltd | Transport & logistics | 2018 |
| M11 Prestige UK Ltd | Transport & logistics | 2024 |
| M23 Entertainment Ltd | Wholesale & retail | 2020 |
| M3 Strategies Limited | Information & communication | 2025 |
| M3T Holdings Ltd | Real estate | 2026 |
| M4GT Limited | Financial services | 2016 |
| M4PPC Limited | Information & communication | 2025 |
| M73A Ltd | Health & social care | 2023 |
| M83 Engineering Limited | Manufacturing | 2018 |
| MA Auction Ventures UK Ltd | Real estate | 2025 |
| MA64 Industry Ltd | Wholesale & retail | 2024 |
| MAA Tara Solutions Ltd | Transport & logistics | 2025 |
| Maaha Limited | Other services | 2025 |
| Maajos Kitchen Limited | Manufacturing | 2023 |
| Maars Properties Ltd | Real estate | 2022 |
| Maashoo Holdings Limited | Real estate | 2021 |
| Mabels Bar Bistro Ltd | Hospitality | 2024 |
| Mabel’S Walk Management Company Limited | Households | 2023 |
| Macandmoore LDN Ltd | Wholesale & retail | 2020 |
| Macarena DE LA Vega Limited | Health & social care | 2017 |
| Macde Ltd | Information & communication | 2013 |
| Mace Construction Limited | Construction | 2024 |
| Machine Mischief Labs Ltd | Manufacturing | 2026 |
| Mackenzie Paige Interiors Ltd | Professional & scientific | 2022 |
| MAD Dog Wins Ltd | Information & communication | 2025 |
| MAD Rodent Ltd | Wholesale & retail | 2026 |
| Madbuilt Limited | Wholesale & retail | 2022 |
| Maddali Innovations Ltd | Manufacturing | 2024 |
| Made for Pets Ltd | Manufacturing | 2022 |
| Made to BE Pampered Limited | Wholesale & retail | 2024 |
| Madennjax Limited | Construction | 2022 |
| Madgem Ltd | Other services | 2024 |
| Madheka Care Ltd | Health & social care | 2018 |
| Madison AI Ltd | Information & communication | 2026 |
| Madni Fairyland Developers and Builders Ltd | Construction | 2026 |
| Madowclo Limited | Wholesale & retail | 2024 |
| Madoz Businesses Limited | Wholesale & retail | 2022 |
| Maekes Ltd | Information & communication | 2025 |
| Maenen Labs Ltd | Information & communication | 2026 |
| Maestro Logic Limited | Information & communication | 2007 |
| Maeve Ryan Consulting Ltd | Professional & scientific | 2021 |
| Mafazaa Ltd | Information & communication | 2025 |
| Maftech Ltd | Information & communication | 2014 |
| Magalore Ltd | Information & communication | 2024 |
| Magdalina's Scented WAX Ltd | Other services | 2022 |