An information processing system relates to a delivery service in which a vehicle cabin including a trunk of a vehicle used by a user is designated as a delivery destination of a package. The information processing system includes a center server configured to remind the user to receive the package from the vehicle cabin of the vehicle designated by the user as the delivery destination of the package, in a case where the package is not received from the vehicle cabin of the vehicle after a predetermined time has elapsed since the package was delivered to the vehicle cabin of the vehicle.