Home Postcodes by state NSW 2289 Postcode 2289 2289 is the postcode for 7 localities in NSW: Adamstown, Adamstown Heights, Garden Suburb, Highfields, Kotara, Kotara Fair and 1 more. Localities with postcode 2289AdamstownNSWAdamstown HeightsNSWGarden SuburbNSWHighfieldsNSWKotaraNSWKotara FairNSWKotara SouthNSW Postcode 2289 State or territory New South Wales (NSW) Localities 7 Council area Newcastle; Mainly Newcastle, partly Lake Macquarie; Lake Macquarie Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 2287 · Postcode 2290