A belt retractor unit with a housing, a rotatably mounted belt reel, a blocking unit for blocking the belt reel, wherein the blocking unit has an electrically controllable actuator unit, a control apparatus for controlling the actuator unit, which has a sensor apparatus for measuring at least one horizontal acceleration value and a switching apparatus for controlling the actuator unit in dependence on at least the at least one horizontal acceleration value, wherein the belt retractor unit has a first emergency state, in which the magnitude of the horizontal acceleration value is above a first limit value and in which the belt reel is blocked, and an unblocking state in which the magnitude of the horizontal acceleration value is below the first limit value.