Home Postcodes by state WA 6528 Postcode 6528 6528 is the postcode for 3 localities in WA: Mount Hill, South Greenough and Walkaway. Localities with postcode 6528Mount HillWASouth GreenoughWAWalkawayWA Postcode 6528 State or territory Western Australia (WA) Localities 3 Council area Greater Geraldton Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 6525 · Postcode 6530