Unfortionatly I'm within city limits and not far from work, so I average 20 city miles daily back and forth in my 2001 Silverado. So that puts me somewhere about 13 mpg. Over the highway though I get between 17.5 and 19, traveling at 70 MPH. I'm sure the camper shell is helping cut into that. But for the size of the vehicle it really isn't bad.