Home Postcodes by state WA 6606 Postcode 6606 6606 is the postcode for 3 localities in WA: Ballidu, East Ballidu and West Ballidu. Localities with postcode 6606BalliduWAEast BalliduWAWest BalliduWA Postcode 6606 State or territory Western Australia (WA) Localities 3 Council area Wongan-Ballidu Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 6605 · Postcode 6608