The difference is actorFor for looking up remote actor is deprecated and replacement is actorSelection. So ActorRef represents a created actor and ActorSelection represents a looked up actor by its path or address. The more subtle difference is, an actor looked up by an actor selection can be sent messages even after it was resurrected (died and came to life). On the other hand actor refs pointing to an actor once dead can not be sent messages even if it is resurrected. This is specific to newer releases of akka.