Home Postcode finder WA De Grey De Grey postcode WA De Grey is a locality in Western Australia covered by postcode 6722. Postcode 6722 State or territory Western Australia (WA) Region North West Suburbs Add a free De Grey business listing Be the first listing in De Grey Common questionsWhat is the postcode for De Grey?De Grey, WA has the postcode 6722.What state is De Grey in?De Grey is in Western Australia (WA).Does postcode 6722 cover more than one suburb?Yes. Postcode 6722 covers 5 localities, so the postcode alone does not identify De Grey. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.