Forum Discussion
connectivity problems outside the USA with apple watch ultra when its standing alone
ultra won't connect to cell towers in other countries
This is what I found:
To cover the LTE and UMTS bands used around the world, there are two separate cellular models for Apple Watch Series 8, Apple Watch SE, and Apple Watch Ultra. They have been optimized for use in the country of purchase, and not all models work in all countries or regions. There is no single model that supports cellular service worldwide. To see which carriers in your country or region offer cellular service for Apple Watch, refer to the chart below.3
