Home Postcodes by state SA 5161 Postcode 5161 5161 is the postcode for 3 localities in SA: Old Reynella, Reynella and Reynella East. Localities with postcode 5161Old ReynellaSAReynellaSAReynella EastSA Postcode 5161 State or territory South Australia (SA) Localities 3 Council area Onkaparinga Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 5160 · Postcode 5162