All-terrain tires are designed to work best off the road while all-season tires are designed to work best on the road. The intended use for the tire best determines what type to buy.
All-terrain tires are generally designed to work well on a variety of surfaces, leading to a more open grip pattern with increased resistance to hydroplaning. They are designed for better off-road performance.
All-season tires focus on only pavement driving and are designed to work in many different weather conditions. They are not optimized for off-road performance.
Rolling resistance is how much friction the tire causes moving across the pavement. All-season tires generally rank higher in rolling resistance, which provides savings in fuel spent to move the vehicle.
All-season tires provide better handling on pavement than the all-terrain tires, and all-season tires brake faster as well. All-terrain tires tend to provide better braking in water, helping prevent hydroplaning.
Overall, both types of tires perform better in the areas they were designed to, all-terrain off road and all-season on road. Buy the tires designed for where they will be used. Tire performance varies widely; be sure to research individual tires more than general use.
