Home Postcodes by state VIC 3431 Postcode 3431 3431 is the postcode for Riddells Creek, VIC. Localities with postcode 3431Riddells CreekVIC Postcode 3431 State or territory Victoria (VIC) Localities 1 Council area Macedon Ranges Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 3430 · Postcode 3432