Apple watch cellular

The Series 9 and Ultra 2 have the same model number for both U.S. Canada, Mexico and Puerto Rico as the rest of the world.

This is different from in the past. See

https://www.apple.com/watch/cellular

We do not know if this means the same Apple Watch model will work anywhere in the world, or if there are special situations that will affect using an Apple Watch in a different country.

Also the warranty is country specific, so you may or may not be able to get warranty support in a country different from where you purchased the Apple Watch.

Finally some countries put restrictions on what features may be used on an Apple Watch, so you may want to check the feature list

https://www.apple.com/watchos/feature-availability

But for the Ultra 1 and Series 8 back to the Series 3, there were 2 models, and they could not be used in the wrong region.

no, people report there are 2 types of apple watch models with cellular

1 which can be used in usa, canada, mexico and porto rico

and

one which can be used in the rest of the world