| Misa B Ltd | Transport & logistics | 2018 |
| Miss Nails Coby Limited | Other services | 2024 |
| Miti Group Ltd | Transport & logistics | 2018 |
| Mizu Capital Limited | Wholesale & retail | 2025 |
| MJ & Co Holdings Ltd | Real estate | 2019 |
| MJE Productions Limited | Arts & recreation | 2001 |
| MJG Management Consultants Limited | Professional & scientific | 2025 |
| Mjpa Holdings Limited | Financial services | 2026 |
| Mjparrott Ltd | Transport & logistics | 2024 |
| MJS Engineering Group Ltd | Manufacturing | 2026 |
| MK &TC Sales Solution Limited | Other services | 2018 |
| MK Europe Ltd | Construction | 2013 |
| MK EUROPE2 Ltd | Construction | 2025 |
| MK Professional Car Sprayer Ltd | Wholesale & retail | 2022 |
| MKF Trans Ltd | Transport & logistics | 2016 |
| MKJ Properties Services Limited | Real estate | 2026 |
| MKJ Services Limited | Real estate | 2015 |
| MKL Trinity Global Ltd | Manufacturing | 2018 |
| MKL Trinity Ltd | Manufacturing | 2017 |
| ML Food Kettering Ltd | Administrative & support | 2016 |
| ML Foods Corby Limited | Hospitality | 2015 |
| Mlsp Properties Ltd | Financial services | 2025 |
| MMC Care Providers Ltd | Health & social care | 2022 |
| Mmgv Limited | Transport & logistics | 2025 |
| MMK Alliance Ltd | Transport & logistics | 2025 |
| MMK Smart Repair Ltd | Wholesale & retail | 2014 |
| MML Pro Ltd | Real estate | 2025 |
| MNT Vehicles Ltd | Wholesale & retail | 2026 |
| Moanv Limited | Wholesale & retail | 2023 |
| Mobile Data Centre Ltd | Wholesale & retail | 2024 |
| Mobile& Tablets Corby Limited | Wholesale & retail | 2024 |
| Modern Cosy Home Ltd | Wholesale & retail | 2026 |
| Modular Project Services Ltd | Professional & scientific | 2020 |
| Moduloc Ltd | Wholesale & retail | 2024 |
| Molla Building Ltd. | Construction | 2014 |
| Momentum A2 Limited | Construction | 2018 |
| Mon+Jon Ltd | Real estate | 2025 |
| Mona Interim Limited | Professional & scientific | 2026 |
| Mondelivery Ltd | Transport & logistics | 2022 |
| Monica Masca Ltd | Wholesale & retail | 2010 |
| MONITOR24 Limited | Education | 2025 |
| Montainbreeze Ltd | Construction | 2022 |
| Moore East Midlands Trustees Limited | Administrative & support | 2004 |
| Mopetpet Limited | Wholesale & retail | 2020 |
| MOR & MOL Ltd | Health & social care | 2025 |
| Mordanmike Services Limited | Health & social care | 2021 |
| Morgan Trading Limited | Information & communication | 2024 |
| Morriss Ltd | Administrative & support | 2019 |
| Mortgage Saint Limited | Financial services | 2023 |
| Moses Phill Services Limited | Real estate | 2018 |
| Motivate Safety Ltd | Administrative & support | 2016 |
| Moto Bike Service Limited | Wholesale & retail | 2020 |
| Motoenc Ltd | Construction | 2025 |
| Motorparts Corby Limited | Wholesale & retail | 2024 |
| Motorzone Kettering Limited | Wholesale & retail | 2013 |
| Movement and Motor Services Limited | Wholesale & retail | 2010 |
| MPC Consultants Ltd | Construction | 2019 |
| MPC One Limited | Professional & scientific | 2011 |
| Mphatso Ltd | Health & social care | 2020 |
| MR B Sikora V Oscar Ltd | Transport & logistics | 2022 |
| MR Barry Mann LLP | | 2020 |
| MR H'S HOG Roast Co. Limited | Hospitality | 2016 |
| MR Hewes Limited | Information & communication | 2024 |
| MR. & MRS. P Ltd | Wholesale & retail | 2022 |
| Mroz Supermarket Ltd | Wholesale & retail | 2019 |
| Msbs Services Ltd | Professional & scientific | 2017 |
| MSC Developments Ltd | Construction | 2025 |
| MSC Groundworks Ltd | Construction | 2016 |
| MSD (Midlands) Wholesale Ltd | Wholesale & retail | 2015 |
| Msmartinex Ltd | Transport & logistics | 2021 |
| Mspc Limited | Hospitality | 2013 |
| Mspc-Properties Ltd | Real estate | 2023 |
| Mtec Renewables Limited | Administrative & support | 2023 |
| Mullahead Property Company Limited | Administrative & support | 2006 |
| Multy UK Ltd | Manufacturing | 1986 |
| Mum's Motors Limited | Wholesale & retail | 2026 |
| MUNZUR23 Ltd | Hospitality | 2024 |
| MUR MUR Flower Ltd | Wholesale & retail | 2026 |
| Mura Health Ltd | Health & social care | 2022 |
| Muraru Couriers Ltd | Transport & logistics | 2019 |
| Murphy Estates (Commercial) Limited | Other services | 2016 |
| Murphy Estates (Residential) Limited | Real estate | 1997 |
| Mursoi Ltd | Transport & logistics | 2025 |
| Murwira Ltd | Health & social care | 2012 |
| Muse Limited | Professional & scientific | 2003 |
| Museums & Galleries Limited | Information & communication | 2013 |
| Music on Earth Productions Ltd | Arts & recreation | 1994 |
| Mustafa Worldwide Limited | Wholesale & retail | 2025 |
| Muto Investments Limited | Financial services | 2020 |
| MW Vehicle Tech Limited | Wholesale & retail | 2018 |
| Mwihaki Ltd | Health & social care | 2011 |
| My Haven House Ltd | Real estate | 2018 |
| MYA Healthcare Limited | Health & social care | 2013 |
| Mycz-Cars Ltd | Wholesale & retail | 2022 |
| Myreco Healthcare Ltd | Health & social care | 2025 |
| Myrkon Ltd | Transport & logistics | 2023 |
| Myrtle & Broadway Limited | Professional & scientific | 2013 |
| N & B Strategic Properties Limited | Real estate | 2016 |
| N & KO Limited | Manufacturing | 2015 |
| N F & I H Ltd. | Professional & scientific | 2015 |