Home Postcode finder SA Walloway Walloway postcode SA Walloway is a locality in South Australia covered by postcode 5431. Postcode 5431 State or territory South Australia (SA) Region SA Outer Suburbs Add a free Walloway business listing Be the first listing in Walloway Common questionsWhat is the postcode for Walloway?Walloway, SA has the postcode 5431.What state is Walloway in?Walloway is in South Australia (SA).Does postcode 5431 cover more than one suburb?Yes. Postcode 5431 covers 14 localities, so the postcode alone does not identify Walloway. Browse other postcodes in South Australia, or widen the search to every Australian postcode.