Home Postcode finder SA Robertstown Robertstown postcode SA Robertstown is a locality in South Australia covered by postcode 5381. Postcode 5381 State or territory South Australia (SA) Region Sa Subs Near 1 Add a free Robertstown business listing More business listings in Robertstown Businesses in RobertstownRobertstown Primary School3 Corey St · 08 85817127 Common questionsWhat is the postcode for Robertstown?Robertstown, SA has the postcode 5381.What state is Robertstown in?Robertstown is in South Australia (SA).Does postcode 5381 cover more than one suburb?Yes. Postcode 5381 covers 9 localities, so the postcode alone does not identify Robertstown. Browse other postcodes in South Australia, or widen the search to every Australian postcode.