Can I use Unicom to move abroad?

Domestic Unicom and mobile users can use it abroad, but they need to open international roaming service in advance, which is expensive to use abroad.

China Unicom and China Mobile have no signal coverage abroad. In foreign countries, they need to use the network that local operators cooperate with domestic operators, which is a high-priced lease, so the cost is higher.

If you use it abroad for a long time, it is recommended to apply for a local mobile phone card.