Home Postcode finder QLD Black Jack Black Jack postcode QLD Black Jack is a locality in Queensland covered by postcode 4820. Postcode 4820 State or territory Queensland (QLD) Region North QLD Add a free Black Jack business listing Be the first listing in Black Jack Common questionsWhat is the postcode for Black Jack?Black Jack, QLD has the postcode 4820.What state is Black Jack in?Black Jack is in Queensland (QLD).Does postcode 4820 cover more than one suburb?Yes. Postcode 4820 covers 21 localities, so the postcode alone does not identify Black Jack. Browse other postcodes in Queensland, or widen the search to every Australian postcode.