Home Postcodes by state NSW 2843 Postcode 2843 2843 is the postcode for Coolah, NSW. Localities with postcode 2843CoolahNSW Postcode 2843 State or territory New South Wales (NSW) Localities 1 Council area Warrumbungle Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 2842 · Postcode 2844