Home Postcodes by state SA 5661 Postcode 5661 5661 is the postcode for 5 localities in SA: Koolgera, Pimbaacla, Wallala, Wirrulla and Yantanabie. Localities with postcode 5661KoolgeraSAPimbaaclaSAWallalaSAWirrullaSAYantanabieSA Postcode 5661 State or territory South Australia (SA) Localities 5 Council area Streaky Bay; Ceduna Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 5660 · Postcode 5670