Home Postcode finder SA Silverton Silverton postcode SA Silverton is a locality in South Australia covered by postcode 5204. Postcode 5204 State or territory South Australia (SA) Region Adelaide Add a free Silverton business listing Be the first listing in Silverton Common questionsWhat is the postcode for Silverton?Silverton, SA has the postcode 5204.What state is Silverton in?Silverton is in South Australia (SA).Does postcode 5204 cover more than one suburb?Yes. Postcode 5204 covers 10 localities, so the postcode alone does not identify Silverton. Browse other postcodes in South Australia, or widen the search to every Australian postcode.