Home Postcode finder WA Strelley Strelley postcode WA Strelley is a locality in Western Australia covered by postcode 6721. Postcode 6721 State or territory Western Australia (WA) Region North West Suburbs Add a free Strelley business listing Be the first listing in Strelley Common questionsWhat is the postcode for Strelley?Strelley, WA has the postcode 6721.What state is Strelley in?Strelley is in Western Australia (WA).Does postcode 6721 cover more than one suburb?Yes. Postcode 6721 covers 8 localities, so the postcode alone does not identify Strelley. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.