Home Postcodes by state SA 5019 Postcode 5019 5019 is the postcode for 4 localities in SA: Exeter, Semaphore, Semaphore Park and Semaphore South. Localities with postcode 5019ExeterSASemaphoreSASemaphore ParkSASemaphore SouthSA Postcode 5019 State or territory South Australia (SA) Localities 4 Council area Port Adelaide Enfield; Charles Sturt Council area based on Australian Bureau of Statistics data (ASGS Edition 3), CC BY 4.0. Postcode 5018 · Postcode 5020