11:Nissan Micra:

The Micra may be a tiny fun box with its unique interior and design but it is actually a good investment when it comes to fuel-efficient cars. It has an EPA rating of up to 88.3 mpg and a 1.5 liter dCi engine. The size actually really matters when it comes to economical cars because you want it not to drag so that less air is forced by it but even then so when you’re riding a car it is best not to put down the windows when on a highway this will too cost you more gas on the pedal because of the larger amount of air that is being dragged.