Home Postcodes by state WA 6057 Postcode 6057 6057 is the postcode for 2 localities in WA: High Wycombe and Maida Vale. Localities with postcode 6057High WycombeWAMaida ValeWA Postcode 6057 State or territory Western Australia (WA) Localities 2 Council area Kalamunda Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 6056 · Postcode 6058