Depending on the thickness of the chicken breast, it generally takes only 2-3 minutes per side for thinner breasts to cook on a hot grill. Thicker breasts can take up to 5 minutes.
If grilling multiple chicken breasts at a time, it helps to even cooking times by flattening the breasts to the same thickness. The chicken breast is done when it turns a solid white color and loses all of the pink tint. Another way to ensure that a breast is cooked through is to use a meat thermometer to check for an internal temperature of roughly 160 degrees Fahrenheit..