Home Postcodes by state WA 6312 Postcode 6312 6312 is the postcode for 9 localities in WA: Boundain, Dumberning, Hillside, Minigin, Narrogin, Narrogin Valley and 3 more. Localities with postcode 6312BoundainWADumberningWAHillsideWAMiniginWANarroginWANarrogin ValleyWANomans LakeWAToolibinWAYilliminningWA Postcode 6312 State or territory Western Australia (WA) Localities 9 Council area Narrogin; Wickepin Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 6311 · Postcode 6313