On weekdays, the M operates between 71st Avenue in Forest Hills, Queens and Metropolitan Avenue in Middle Village, Queens, via the IND Queens Boulevard and Sixth Avenue lines, the Williamsburg Bridge, and the BMT Jamaica and BMT Myrtle Avenue lines (making it the only service that travels in one borough twice via two different lines).
М следует по линиям: IND Queens Boulevard, Sixth Avenue lines, Williamsburg Bridge, BMT Jamaica и Myrtle Avenue lines.