Home Postcodes by state NSW 2120 Postcode 2120 2120 is the postcode for 3 localities in NSW: Pennant Hills, Thornleigh and Westleigh. Localities with postcode 2120Pennant HillsNSWThornleighNSWWestleighNSW Postcode 2120 State or territory New South Wales (NSW) Localities 3 Council area Hornsby Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 2119 · Postcode 2121