Home Postcode finder NSW Castle Rock Castle Rock postcode NSW Castle Rock is a locality in New South Wales covered by postcode 2333. Postcode 2333 State or territory New South Wales (NSW) Region Hunter Add a free Castle Rock business listing Be the first listing in Castle Rock Common questionsWhat is the postcode for Castle Rock?Castle Rock, NSW has the postcode 2333.What state is Castle Rock in?Castle Rock is in New South Wales (NSW).Does postcode 2333 cover more than one suburb?Yes. Postcode 2333 covers 14 localities, so the postcode alone does not identify Castle Rock. Browse other postcodes in New South Wales, or widen the search to every Australian postcode.