Home Postcode finder QLD Blacksoil Blacksoil postcode QLD Blacksoil is a locality in Queensland covered by postcode 4306. Postcode 4306 State or territory Queensland (QLD) Region Western Suburbs Add a free Blacksoil business listing Be the first listing in Blacksoil Common questionsWhat is the postcode for Blacksoil?Blacksoil, QLD has the postcode 4306.What state is Blacksoil in?Blacksoil is in Queensland (QLD).Does postcode 4306 cover more than one suburb?Yes. Postcode 4306 covers 56 localities, so the postcode alone does not identify Blacksoil. Browse other postcodes in Queensland, or widen the search to every Australian postcode.