Do Tonneau Covers Really Boost Your Truck’s MPG, or Is It Just Bro Science?

Pickup truck owners have long debated whether a tonneau cover can squeeze out extra miles per gallon, and the answer isn’t as simple as your uncle’s garage wisdom suggests. While the boxy bed of a truck is a notorious drag on fuel economy, a tonneau cover—specifically lightweight, soft roll-up or folding types—can make a measurable difference. According to RealTruck’s testing, these covers reduce a truck bed’s drag coefficient by about 5%, translating to roughly a 2% improvement in overall fuel economy.

That’s not a huge leap, but over time and long highway drives, it adds up. For example, a *Forbes* writer saw highway MPG on a Ram 1500 TRX jump from 8–9 MPG to 11–12 MPG after installing a tonneau cover, with an overall fuel economy boost of nearly 10% in real-world use. The catch?

Not all covers are created equal. Heavy, rigid models can offset any aerodynamic gains with their added weight, leaving MPG unchanged. And then there’s the cost.

Decent tonneau covers run anywhere from $1,500 to $2,500 depending on bed size, brand, and material—hardly pocket change. At that price, recouping the investment through fuel savings alone could take years, especially if your truck isn’t a daily highway cruiser. Still, tonneau covers aren’t just about MPG.

They lock down cargo, shield it from weather, and turn the bed into a pseudo-trunk, which is a major perk for anyone who uses their truck more for weekend adventures than workaday hauling. So while the fuel economy boost is real—albeit modest—it’s just one slice of the tonneau cover’s appeal.