Home Postcode finder SA The Gap The Gap postcode SA The Gap is a locality in South Australia covered by postcode 5271. Postcode 5271 State or territory South Australia (SA) Region SA Outer Suburbs Add a free The Gap business listing Be the first listing in The Gap Common questionsWhat is the postcode for The Gap?The Gap, SA has the postcode 5271.What state is The Gap in?The Gap is in South Australia (SA).Does postcode 5271 cover more than one suburb?Yes. Postcode 5271 covers 18 localities, so the postcode alone does not identify The Gap. Browse other postcodes in South Australia, or widen the search to every Australian postcode.