Is your child ready for a belt-positioning booster seat? Congratulations! Your days of struggling to fit car seats into your vehicle are mostly over. Unlike infant or convertible child safety seats, most belt-positioning (not harnessed) boosters require little or no installation. But a good fit is still critical.

A good belt-positioning booster should position the shoulder portion of a three-point vehicle safety belt right in the middle of a child’s shoulder, not too close to the neck or too far out on the shoulder or arm. The lap portion of the belt should lie across the upper thighs and hips, not the abdomen. (This applies to adults, too.) And the child’s knees should be able to bend comfortably over the edge of the booster seat. If they don’t the child might slouch, which can compromise safety if the lap belt moves up to the abdomen.

See our booster seat Ratings, and learn more about booster seat installation and fit.