Home Postcodes by state QLD 4078 Postcode 4078 4078 is the postcode for 2 localities in QLD: Ellen Grove and Forest Lake. Localities with postcode 4078Ellen GroveQLDForest LakeQLD Postcode 4078 State or territory Queensland (QLD) Localities 2 Council area Brisbane Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 4077 · Postcode 4101