In the case of foreigners want to travel aboard for a short period, they need to apply for re-entry permit before leaving Thailand. It is to keep their stay permit (Non-Ed/Non-B) in Thailand. If they are not applied, their visa will automatically be canceled although it has not expired.
When applying for a re-entry permit, they need to submit documents as follows:
1. Passport and one copy of first page, visa page, latest entry visa
2. Application form T.M. 8
3. 1 photo (4x6 cm)
4. Re-entry permit fee (1,000 THB for single entry/ 3,800 THB for multiple entries)
Please note that the foreigners must apply re-entry permit in person at the Office of Immigration, Bangkok. When they return to Thailand, they should check re-entry permit number on T.M.6 card that are stamped correctly.