Home Postcodes by state VIC 3103 Postcode 3103 3103 is the postcode for 3 localities in VIC: Balwyn, Balwyn East and Deepdene. Localities with postcode 3103BalwynVICBalwyn EastVICDeepdeneVIC Postcode 3103 State or territory Victoria (VIC) Localities 3 Council area Boroondara Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 3102 · Postcode 3104