Home Postcode finder QLD Millmerran Downs Millmerran Downs postcode QLD Millmerran Downs is a locality in Queensland covered by postcode 4357. Postcode 4357 State or territory Queensland (QLD) Region Toowoomba Region Add a free Millmerran Downs business listing Be the first listing in Millmerran Downs Common questionsWhat is the postcode for Millmerran Downs?Millmerran Downs, QLD has the postcode 4357.What state is Millmerran Downs in?Millmerran Downs is in Queensland (QLD).Does postcode 4357 cover more than one suburb?Yes. Postcode 4357 covers 26 localities, so the postcode alone does not identify Millmerran Downs. Browse other postcodes in Queensland, or widen the search to every Australian postcode.