Home Postcodes by state NSW 2401 Postcode 2401 2401 is the postcode for Gravesend, NSW. Localities with postcode 2401GravesendNSW Postcode 2401 State or territory New South Wales (NSW) Localities 1 Council area Gwydir Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 2400 · Postcode 2402