Home Postcode finder SA Durham Downs Durham Downs postcode SA Durham Downs is a locality in South Australia covered by postcode 5731. Postcode 5731 State or territory South Australia (SA) Region SA Outer Suburbs Add a free Durham Downs business listing Be the first listing in Durham Downs Common questionsWhat is the postcode for Durham Downs?Durham Downs, SA has the postcode 5731.What state is Durham Downs in?Durham Downs is in South Australia (SA).Does postcode 5731 cover more than one suburb?Yes. Postcode 5731 covers 9 localities, so the postcode alone does not identify Durham Downs. Browse other postcodes in South Australia, or widen the search to every Australian postcode.