Mack (II)
    1954-1964
    Mack Trucks (Great Britain) Ltd
    Barking, Essex

Magirus-Deutz (III)
    1974-
    Magirus-Deutz (Great Britain)

Maltby
    1905-1922
    Maltby's Motor Works
    Sandgate, Kent

Manchester (I)
    1905
    Turner, Atherton & Co Ltd
    Denton, Manchester

Manchester (II)
    1928-1933
    Willys-Overland-Crossley Ltd
    Heaton Chapel Stockport, Cheshire

Manchester GNU
    1973-1975
    Nigel Engineering Co Ltd
    Swinton, Manchester

Mann (I)
    1897-1926
    Mann & Charlesworth Ltd
    Hunslet, Leeds, Yorkshire

Mann (II)
    1907-1908
    G H Mann
    Holbeck, Leeds, Yorkshire

Manton
    1946-1951
    Manton Motors Ltd
    Croydon, Surrey

Manulectric
    1953-n. 1963
    Electric Vehicles
    Brighton, Sussex

Maratohon (II)
    1920-1925
    James Walmsley & Co Ltd
    Preston, Lancashire

Martin (II)
    1925-1926
    Martins Cultivators Ltd
    Stamford, Lincolnshire

Martyn
    1898
    David Martyn & Co Ltd
    Hebburn-on-Tyne, Co Durham

Maudslay
    1903-1960
    Maudslay Motor Co Ltd
    Parkside, Coventry

Maudslay & Field
    1833-1835
    Lontoo

McCurd
    1912-1921, 1925-1927
    W A McCurd
    Hayes, Middlesex

McLaren
    1940
    J & H McLaren Ltd
    Leeds, Yorkshire

MCW
    1938-
    Metropolitan Cammel Carriage Wagon & Finance Co Ltd, Birmingham ja
    Weymann's Motor Bodies Ltd, Addlestone, Surrey

M & D
    1925-1927
    Rhode Motor Co Ltd
    Tyseley, Birmingham

Mendip
    1907-1908, 1912-n. 1913
    C W Harris, Chewton Mendip
    Somerset

Mercury
    1920-1964

Merryweather
    1899
    Merryweather & Sons Ltd
    Lontoo

Metro-Scania
    1970-1977
    Metro-Cammel-Weymann Ltd
    Birmingham

Metrovick
    1934-1942
    Metropolitan-Vickers Electrical Co Ltd
    Trafford Park, Manchester

Michigan
    1951-

Midland Electric
    n. 1935-n. 1958
    Midland Vehicles Ltd
    Leamington Spa, Warwickshire

Millars
    1927-1936

Milnes
    1901-1902
    G F Milnes & Co Ltd
    Wellington, Salop

Milnes-Daimler
    1902-1916
    Milnes-Daimler Ltd
    Wellington, Slop

Mini
    1975-
    Austin-Rover Ltd
    Coventry

M & J
    1908
    Martin & Jellicoe Ltd
    Thames Ditton, Surrey

MMC
    1898-1908
    Motor Mfg Co Ltd
    Coventry

MOC
    1906-1907
    Motor Omnibus Construction Ltd
    Walthamstow, Lontoo

MOC-Crompton
    1909

Modern Wheel Drive
    1924-1932

Morris (I)
    n. 1956-1968
    Morris Commercial Cars Ltd
    Birmingham

Morris-Commercial
    1924-1954
    Morris Commercial Cars Ltd
    Soho, Birmingham

Morrison
    1933
    A E ja A C Morrison
    Leicestershire

Morrison-Electric
    1934-1941
    A E Morrison & Sons
    Leicestershire

Morrison-Electricar
    1941-n. 1972
    Associated Electric Vehicle Manufacturers
    South Wigston, Leicestershire

Morriss
    1899-n. 1901
    Frank Morriss
    King's Lynn, Norfolk

Morton
    n. 1900-1907

Motil
    1980-

Motor Rail
    1948-?