I'll be traveling to SE Asia, and want one phone service. If I buy a SIM card with Viettel in Vietnam, will it function in Thailand and in Laos and in Cambodia?
If it does, will I be charged roaming?
Travel Stack Exchange is a question and answer site for road warriors and seasoned travelers. It only takes a minute to sign up.Sign up to join this community
As of 2017-01-11 Yes and partial yes.
There are no universal SIM cards in SE Asia.
However, from 2017-01-01, Viettel
removed reduced roaming charge in Vietnam, Laos, Cambodia.
The new fee can be found here (unfortunately it's in Vietnamese) in tab "Cước Roaming Đông Dương".
The new fee is: