Home Postcodes by state SA 5171 Postcode 5171 5171 is the postcode for 5 localities in SA: Blewitt Springs, Mclaren Flat, Mclaren Vale, Pedler Creek and Tatachilla. Localities with postcode 5171Blewitt SpringsSAMclaren FlatSAMclaren ValeSAPedler CreekSATatachillaSA Postcode 5171 State or territory South Australia (SA) Localities 5 Council area Onkaparinga Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 5170 · Postcode 5172