Do I need Tibet travel permits to fly from Lhasa to Kathmandu?
When you fly from Lhasa to Kathmandu, Nepal, the airport custom will check passports, your China visa, Tibet permits (including entry permit and border defense permit), however guide will need to show these permits and help you clear the customs easily. After that, guide will take permits back. Hope this helps. Any reliable Tibet travel agencies here in Lhasa know very well.