Home Postcode finder WA Mount Hardman Mount Hardman postcode WA Mount Hardman is a locality in Western Australia covered by postcode 6765. Postcode 6765 State or territory Western Australia (WA) Region North West Suburbs Add a free Mount Hardman business listing Be the first listing in Mount Hardman Common questionsWhat is the postcode for Mount Hardman?Mount Hardman, WA has the postcode 6765.What state is Mount Hardman in?Mount Hardman is in Western Australia (WA).Does postcode 6765 cover more than one suburb?Yes. Postcode 6765 covers 2 localities, so the postcode alone does not identify Mount Hardman. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.