Buying Apple Watch In USA

Just to back up @Phil0124, DO NOT buy a cellular version of Apple Watch in USA and expect it to work in Australia. The North American cellular frequencies are incompatible with Australian networks, so it is unlikely to work correctly. The USA models A1860 and A1861 are approved by FCC in USA but not approved by Australian regulators and it is likely the Australian networks will be unable to activate the watch.

See this about the versions of the Apple Watch and their use with cellular providers. Apple Watch - Carriers - Apple The US version and the Australian version are different. You would not be able to use the US version with a carrier in Australia. They are two different devices. If you wish to use an Apple Watch with cellular in Australia, you will need to purchase the device in Australia.

That is correct. The US version supports US celular bands which are different to Australian cellular bands.

Even if if the Australian carrier agrees to achívate it with their service, it is possible it would not correctly work.

If You want to use cellular in Australia, you will need to buy the Australian model that supports the cell bands there.

Yes, you do not have to activate the cellular portion until you are ready. The Watch will still work with the iPhone, and will do everything that the other Watches would do when with their paired phones. Once you return to Australia, you can contact your carrier and see about activating the cellular portion if desired.

I'm sorry, when you said buy it here, I interpreted that as meaning you are still in Australia. I had no idea you were already in the US. I'm sorry if I confused that. I stand by what I said earlier, a purchase of a Watch in the US will not work in Australia. Sorry for that confusion.