M6

M6 or M-6 may mean:

In roads:

 M6 motorway, a motorway in the United Kingdom
 M6 Toll, a toll motorway in the United Kingdom that relieves traffic on the M6 motorway
 M6 (Ireland), a motorway-grade section of the N6 road in the Republic of Ireland
 M6 motorway (Hungary), a motorway in Hungary
 M-6 (Michigan highway), a state highway in southern Michigan
 Russian route M6 is another name for the Caspian Highway in Russia