Home Postcodes by state QLD 4428 Postcode 4428 4428 is the postcode for 4 localities in QLD: Pickanjinnie, Wallumbilla, Wallumbilla North and Wallumbilla South. Localities with postcode 4428PickanjinnieQLDWallumbillaQLDWallumbilla NorthQLDWallumbilla SouthQLD Postcode 4428 State or territory Queensland (QLD) Localities 4 Council area Maranoa Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 4427 · Postcode 4454