Home Postcode finder SA Frankton Frankton postcode SA Frankton is a locality in South Australia covered by postcode 5374. Postcode 5374 State or territory South Australia (SA) Region Sa Subs Near 1 Add a free Frankton business listing Be the first listing in Frankton Common questionsWhat is the postcode for Frankton?Frankton, SA has the postcode 5374.What state is Frankton in?Frankton is in South Australia (SA).Does postcode 5374 cover more than one suburb?Yes. Postcode 5374 covers 15 localities, so the postcode alone does not identify Frankton. Browse other postcodes in South Australia, or widen the search to every Australian postcode.