Home Postcodes by state WA 6012 Postcode 6012 6012 is the postcode for Mosman Park, WA. Localities with postcode 6012Mosman ParkWA Postcode 6012 State or territory Western Australia (WA) Localities 1 Council area Mosman Park Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 6011 · Postcode 6014