Depends on where you go,
Linzhi
Most tourist areas do not require a border permit, and if you go
Medog
It is only necessary to wait for border areas.
To apply for a border permit, you can apply for it at the Household Registration Section of the Public Security Bureau at the place where your household registration or work unit is registered (the police station does not care about this). Just bring your ID card and two 1-inch photos. On-site application is available and free of charge. It is not recommended to go to Lhasa to apply. Not only does it take 1-2 days, but you also have to pay the travel agency a sum of money. It is completely unnecessary.

However, it should be noted that the border permit is valid for 3 months from the date of application.

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