Home Postcode finder NSW Mardi Mardi postcode NSW Mardi is a locality in New South Wales covered by postcode 2259. Postcode 2259 State or territory New South Wales (NSW) Region Gosford Add a free Mardi business listing Be the first listing in Mardi Common questionsWhat is the postcode for Mardi?Mardi, NSW has the postcode 2259.What state is Mardi in?Mardi is in New South Wales (NSW).Does postcode 2259 cover more than one suburb?Yes. Postcode 2259 covers 42 localities, so the postcode alone does not identify Mardi. Browse other postcodes in New South Wales, or widen the search to every Australian postcode.