Home Postcodes by state QLD 4066 Postcode 4066 4066 is the postcode for 3 localities in QLD: Auchenflower, Mount Coot-Tha and Toowong. Localities with postcode 4066AuchenflowerQLDMount Coot-ThaQLDToowongQLD Postcode 4066 State or territory Queensland (QLD) Localities 3 Council area Brisbane Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 4065 · Postcode 4067