Home Postcode finder SA Cygnet River Cygnet River postcode SA Cygnet River is a locality in South Australia covered by postcode 5223. Postcode 5223 State or territory South Australia (SA) Region Sa Subs Near 2 Add a free Cygnet River business listing Be the first listing in Cygnet River Common questionsWhat is the postcode for Cygnet River?Cygnet River, SA has the postcode 5223.What state is Cygnet River in?Cygnet River is in South Australia (SA).Does postcode 5223 cover more than one suburb?Yes. Postcode 5223 covers 30 localities, so the postcode alone does not identify Cygnet River. Browse other postcodes in South Australia, or widen the search to every Australian postcode.