Home Postcodes by state WA 6358 Postcode 6358 6358 is the postcode for Karlgarin, WA. Localities with postcode 6358KarlgarinWA Postcode 6358 State or territory Western Australia (WA) Localities 1 Council area Kondinin Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 6357 · Postcode 6359