Home Postcode finder NSW Moonan Flat Moonan Flat postcode NSW Moonan Flat is a locality in New South Wales covered by postcode 2337. Postcode 2337 State or territory New South Wales (NSW) Region Hunter Add a free Moonan Flat business listing Be the first listing in Moonan Flat Common questionsWhat is the postcode for Moonan Flat?Moonan Flat, NSW has the postcode 2337.What state is Moonan Flat in?Moonan Flat is in New South Wales (NSW).Does postcode 2337 cover more than one suburb?Yes. Postcode 2337 covers 25 localities, so the postcode alone does not identify Moonan Flat. Browse other postcodes in New South Wales, or widen the search to every Australian postcode.