A brake booster coupling device includes: a braking piston, an input piston displaceable by an operation of a brake input element from its starting position by a driver braking distance, a force transmission between the input piston displaced by a driver braking distance below a predefined threshold value and the braking piston is suppressed, and a booster piston displaceable with the aid of the brake booster drive such that the braking piston, which contacts the booster piston, is displaceable with the aid of the brake booster drive from a non-braking position into a braking position; a contact element displaceable by a displacement of the braking piston from the non-braking position into the braking position such that a first contact surface of the contact element contacts a second contact surface of the input piston in such a way that a driver brake force is transmittable to the braking piston.