Home Postcodes by state SA 5243 Postcode 5243 5243 is the postcode for Oakbank, SA. Postcode 5243 State or territory South Australia (SA) Localities 1 Council area Adelaide Hills Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Localities with postcode 5243OakbankSA Browse postcodes in order← 5242 Balhannah · 5244 Charleston →