Home Postcodes by state WA 6225 Postcode 6225 6225 is the postcode for 18 localities in WA: Allanson, Bowelling, Buckingham, Cardiff, Collie, Collie Burn and 12 more. Localities with postcode 6225AllansonWABowellingWABuckinghamWACardiffWACollieWACollie BurnWAHarris RiverWALyalls MillWAMcalindenWAMujaWAMumballupWAMungalupWANoggerupWAPalmerWAPreston SettlementWAShottsWAWorsleyWAYourdamung LakeWA Postcode 6225 State or territory Western Australia (WA) Localities 18 Council area Collie; West Arthur; Boyup Brook; Donnybrook-Balingup Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 6224 · Postcode 6226