Home Postcode finder SA Steelton Steelton postcode SA Steelton is a locality in South Australia covered by postcode 5413. Postcode 5413 State or territory South Australia (SA) Region Sa Subs Near 1 Add a free Steelton business listing Be the first listing in Steelton Common questionsWhat is the postcode for Steelton?Steelton, SA has the postcode 5413.What state is Steelton in?Steelton is in South Australia (SA).Does postcode 5413 cover more than one suburb?Yes. Postcode 5413 covers 9 localities, so the postcode alone does not identify Steelton. Browse other postcodes in South Australia, or widen the search to every Australian postcode.