Home Postcodes by state WA 6428 Postcode 6428 6428 is the postcode for Babakin, WA. Localities with postcode 6428BabakinWA Postcode 6428 State or territory Western Australia (WA) Localities 1 Council area Bruce Rock Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 6427 · Postcode 6429