Home Postcode finder WA Dunn Rock Dunn Rock postcode WA Dunn Rock is a locality in Western Australia covered by postcode 6355. Postcode 6355 State or territory Western Australia (WA) Region Wa Subs 2 Gsr Add a free Dunn Rock business listing Be the first listing in Dunn Rock Common questionsWhat is the postcode for Dunn Rock?Dunn Rock, WA has the postcode 6355.What state is Dunn Rock in?Dunn Rock is in Western Australia (WA).Does postcode 6355 cover more than one suburb?Yes. Postcode 6355 covers 11 localities, so the postcode alone does not identify Dunn Rock. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.