Home Postcode finder SA Risdon Park South Risdon Park South postcode SA Risdon Park South is a locality in South Australia covered by postcode 5540. Postcode 5540 State or territory South Australia (SA) Region SA Outer Suburbs Add a free Risdon Park South business listing Be the first listing in Risdon Park South Common questionsWhat is the postcode for Risdon Park South?Risdon Park South, SA has the postcode 5540.What state is Risdon Park South in?Risdon Park South is in South Australia (SA).Does postcode 5540 cover more than one suburb?Yes. Postcode 5540 covers 14 localities, so the postcode alone does not identify Risdon Park South. Browse other postcodes in South Australia, or widen the search to every Australian postcode.