Home Postcode finder QLD Blackstone Blackstone postcode QLD Blackstone is a locality in Queensland covered by postcode 4304. Postcode 4304 State or territory Queensland (QLD) Region Western Suburbs Add a free Blackstone business listing Be the first listing in Blackstone Common questionsWhat is the postcode for Blackstone?Blackstone, QLD has the postcode 4304.What state is Blackstone in?Blackstone is in Queensland (QLD).Does postcode 4304 cover more than one suburb?Yes. Postcode 4304 covers 7 localities, so the postcode alone does not identify Blackstone. Browse other postcodes in Queensland, or widen the search to every Australian postcode.