Home Postcodes by state WA 6385 Postcode 6385 6385 is the postcode for Kwolyin, WA. Localities with postcode 6385KwolyinWA Postcode 6385 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 6384 · Postcode 6386