Home Postcodes by state QLD 4123 Postcode 4123 4123 is the postcode for 2 localities in QLD: Rochedale and Rochedale South. Localities with postcode 4123RochedaleQLDRochedale SouthQLD Postcode 4123 State or territory Queensland (QLD) Localities 2 Council area Brisbane; Logan Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 4122 · Postcode 4124