Home Postcode finder SA Murlong Murlong postcode SA Murlong is a locality in South Australia covered by postcode 5642. Postcode 5642 State or territory South Australia (SA) Region SA Outer Suburbs Add a free Murlong business listing Be the first listing in Murlong Common questionsWhat is the postcode for Murlong?Murlong, SA has the postcode 5642.What state is Murlong in?Murlong is in South Australia (SA).Does postcode 5642 cover more than one suburb?Yes. Postcode 5642 covers 5 localities, so the postcode alone does not identify Murlong. Browse other postcodes in South Australia, or widen the search to every Australian postcode.