Home Postcodes by state SA 5558 Postcode 5558 5558 is the postcode for 14 localities in SA: Agery, Cross Roads, East Moonta, Hamley, Kooroona, Moonta and 8 more. Localities with postcode 5558AgerySACross RoadsSAEast MoontaSAHamleySAKooroonaSAMoontaSAMoonta BaySAMoonta MinesSANalyappaSANorth MoontaSANorth YeltaSAParamattaSAPort HughesSAYeltaSA Postcode 5558 State or territory South Australia (SA) Localities 14 Council area Yorke Peninsula; Copper Coast Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 5556 · Postcode 5560