Home Postcodes by state QLD 4721 Postcode 4721 4721 is the postcode for 8 localities in QLD: Argyll, Clermont, Frankfield, Gemini Mountains, Kilcummin, Pasha and 2 more. Localities with postcode 4721ArgyllQLDClermontQLDFrankfieldQLDGemini MountainsQLDKilcumminQLDPashaQLDTheresa CreekQLDWolfangQLD Postcode 4721 State or territory Queensland (QLD) Localities 8 Council area Central Highlands; Isaac Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 4720 · Postcode 4722