Home Postcode finder SA Macdonald Park Macdonald Park postcode SA Macdonald Park is a locality in South Australia covered by postcode 5121. Postcode 5121 State or territory South Australia (SA) Region Sa Subs Near 1 Add a free Macdonald Park business listing Be the first listing in Macdonald Park Common questionsWhat is the postcode for Macdonald Park?Macdonald Park, SA has the postcode 5121.What state is Macdonald Park in?Macdonald Park is in South Australia (SA).Does postcode 5121 cover more than one suburb?Yes. Postcode 5121 covers 3 localities, so the postcode alone does not identify Macdonald Park. Browse other postcodes in South Australia, or widen the search to every Australian postcode.