Home Postcode finder WA Rosa Brook Rosa Brook postcode WA Rosa Brook is a locality in Western Australia covered by postcode 6285. Postcode 6285 State or territory Western Australia (WA) Region Wa Subs 3 Sth Rd Add a free Rosa Brook business listing Be the first listing in Rosa Brook Common questionsWhat is the postcode for Rosa Brook?Rosa Brook, WA has the postcode 6285.What state is Rosa Brook in?Rosa Brook is in Western Australia (WA).Does postcode 6285 cover more than one suburb?Yes. Postcode 6285 covers 9 localities, so the postcode alone does not identify Rosa Brook. Browse other postcodes in Western Australia, or widen the search to every Australian postcode.