I honestly don't know. They do work in Albany, Denmark, Bunbury, and Kalgoorlie. Although you may have to switch to 3G....as being in a crap reception area on the outskirts of Perth, in a small valley - 4G does not work for Telstra or Optus dependably. 4G works fine closer to the city. We are mapped as rubbish - on both of their coverage areas. 3G works great and has worked fine for me in many areas of WA. I could not be bothered to switch to 4G to experiment anywhere else. 3G does fine for calls, general web, email etc...
