Abstract: Keg washers and locking mechanisms for keg washers are disclosed. The keg washers may include a base assembly, a cleaning head, a head mechanism, and a locking mechanism configured to secure the keg to the base assembly. The locking mechanism may include a holder mechanism and a neck holder fixedly mounted to the holder mechanism. The neck holder may include a first opening and a second opening. The holder mechanism may be configured, when the cleaning head is moved from a retracted position toward an extended position, to move the neck holder from a first position in which a first neck portion of a keg is received in the first opening but a second neck portion is not received in the second opening, to a second position in which the first neck portion is received in the first opening and the second neck portion is received in the second opening.