There is an embedded SIM card in the Apple Watch, and while the Apple Sim in iPhones and iPads is designed to make switching carriers easily, that’s not the case with this particular eSIM.
As one MacRumors reader has pointed out, thanks to a conversation they had with an Apple support representative, the Apple Watch Series 3 with LTE will only work in the country, and on the carriers therein, from where it was purchased. So, if you buy your Series 3 with LTE in the United States it will work on the four biggest wireless carriers there, but it will not work on a carrier in Canada, or in Germany, or other international markets.
“If you purchased one (an Apple Watch S3 GPS + Cellular) through the US Apple Online Store, it’ll only work for the 4 US carriers. It wouldn’t work internationally unfortunately. I’m not entirely sure what type of error it would show if you took a US Watch to Germany, but it wouldn’t be compatible with Telekom.”
In addition, the Apple Watch Series 3 with LTE does not support roaming, even in the country where it was purchased, so it won’t let the user roam on a network in another country, either.
For a refresher, the Apple Watch Series 3 with LTE is available in these countries:
- Puerto Rico
- United Kingdom
- United States
The Apple Watch Series 3 with LTE (and without) went up for pre-order earlier today. It goes on sale next week (unless you want a Nike+ variant, which will go on sale in October).