Home Postcode finder WA Garden Island Garden Island postcode WA Garden Island is a locality in Western Australia covered by postcode 6168. Postcode 6168 State or territory Western Australia (WA) Region Wa Subs 3 Sth Rd Add a free Garden Island business listing Be the first listing in Garden Island Common questionsWhat is the postcode for Garden Island?Garden Island, WA has the postcode 6168.What state is Garden Island in?Garden Island is in Western Australia (WA).Does postcode 6168 cover more than one suburb?Yes. Postcode 6168 covers 7 localities, so the postcode alone does not identify Garden Island. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.