Home Postcodes by state SA 5420 Postcode 5420 5420 is the postcode for 2 localities in SA: Canowie Belt and Whyte Yarcowie. Localities with postcode 5420Canowie BeltSAWhyte YarcowieSA Postcode 5420 State or territory South Australia (SA) Localities 2 Council area Goyder Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 5419 · Postcode 5421