The following is a list and description of Quebec autoroutes that were intended to be built but, for one reason or another, never were.
During the 1960s and 1970s, Autoroute 6 was planned to run from Autoroute 15 in La Prairie to Farnham, also intersecting Autoroute 30 and Autoroute 35. It would have paralleled Route 104.
Portion only: The Autoroute 13 was designed to proceed all the way to then new Montreal/Mirabel airport; the section north of Autoroute 640 to the airport was never built. It is unclear whether the highway was to pass underneath the airport or to connect with Autoroute 50 west of the airport.