Home Postcode finder WA Hill River Hill River postcode WA Hill River is a locality in Western Australia covered by postcode 6521. Postcode 6521 State or territory Western Australia (WA) Region Wa Subs 4 Coast Add a free Hill River business listing Be the first listing in Hill River Common questionsWhat is the postcode for Hill River?Hill River, WA has the postcode 6521.What state is Hill River in?Hill River is in Western Australia (WA).Does postcode 6521 cover more than one suburb?Yes. Postcode 6521 covers 5 localities, so the postcode alone does not identify Hill River. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.