Home Postcodes by state SA 5485 Postcode 5485 5485 is the postcode for Wilmington, SA. Localities with postcode 5485WilmingtonSA Postcode 5485 State or territory South Australia (SA) Localities 1 Council area Mount Remarkable Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 5483 · Postcode 5490