Home Postcodes by state NSW 2791 Postcode 2791 2791 is the postcode for 2 localities in NSW: Carcoar and Errowanbang. Localities with postcode 2791CarcoarNSWErrowanbangNSW Postcode 2791 State or territory New South Wales (NSW) Localities 2 Council area Blayney Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 2790 · Postcode 2792