Home Postcode finder QLD Roundstone Roundstone postcode QLD Roundstone is a locality in Queensland covered by postcode 4718. Postcode 4718 State or territory Queensland (QLD) Region Central QLD Add a free Roundstone business listing Be the first listing in Roundstone Common questionsWhat is the postcode for Roundstone?Roundstone, QLD has the postcode 4718.What state is Roundstone in?Roundstone is in Queensland (QLD).Does postcode 4718 cover more than one suburb?Yes. Postcode 4718 covers 9 localities, so the postcode alone does not identify Roundstone. Browse other postcodes in Queensland, or widen the search to every Australian postcode.