Home Postcodes by state VIC 3374 Postcode 3374 3374 is the postcode for Great Western, VIC. Localities with postcode 3374Great WesternVIC Postcode 3374 State or territory Victoria (VIC) Localities 1 Council area Northern Grampians Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 3373 · Postcode 3375