An adjustable head restraint assembly for a vehicle seat is provided with a post for supporting a head restraint for movement along the post. A biasing member is mounted to the head restraint and cooperates with the post for maintaining the head restraint at a locked position. A ramp is fixed to the head restraint within a path of movement of the biasing member. An actuation member is mounted to the head restraint and cooperates with the biasing member for urging the biasing member into engagement with the ramp and consequently out of engagement with the post for permitting movement of the head restraint along the post.