Home Postcodes by state VIC 3104 Postcode 3104 3104 is the postcode for 2 localities in VIC: Balwyn North and Greythorn. Localities with postcode 3104Balwyn NorthVICGreythornVIC Postcode 3104 State or territory Victoria (VIC) Localities 2 Council area Boroondara Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 3103 · Postcode 3105