Home Postcodes by state NSW 2588 Postcode 2588 2588 is the postcode for Wallendbeen, NSW. Localities with postcode 2588WallendbeenNSW Postcode 2588 State or territory New South Wales (NSW) Localities 1 Council area Cootamundra-Gundagai Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 2587 · Postcode 2590