There are many SUVs on market today. To determine which SUV has the best gas mileage, you would need to first consider the size of the vehicle. Smaller SUVs tend to get better mileage, with the hybrids leading the charge. So if you are looking into an SUV, first determine how big you need to go to handle your passengers/cargo requirements. Then compare mileage estimates for those models that fit your needs. Hybrids and 4 cylinder models will range from the mid 20mpgs into the low 30’s, while the larger V8’s will still top out in mid to upper teens.