Home Postcode finder QLD South Gladstone South Gladstone postcode QLD South Gladstone is a locality in Queensland covered by postcode 4680. Postcode 4680 State or territory Queensland (QLD) Region Central QLD Add a free South Gladstone business listing Be the first listing in South Gladstone Common questionsWhat is the postcode for South Gladstone?South Gladstone, QLD has the postcode 4680.What state is South Gladstone in?South Gladstone is in Queensland (QLD).Does postcode 4680 cover more than one suburb?Yes. Postcode 4680 covers 41 localities, so the postcode alone does not identify South Gladstone. Browse other postcodes in Queensland, or widen the search to every Australian postcode.