Home Postcode finder WA Kingston Kingston postcode WA Kingston is a locality in Western Australia covered by postcode 6256. Postcode 6256 State or territory Western Australia (WA) Region Wa Subs 3 Sth Rd Add a free Kingston business listing Be the first listing in Kingston Common questionsWhat is the postcode for Kingston?Kingston, WA has the postcode 6256.What state is Kingston in?Kingston is in Western Australia (WA).Does postcode 6256 cover more than one suburb?Yes. Postcode 6256 covers 6 localities, so the postcode alone does not identify Kingston. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.