I am currently on post-completion F-1 OPT and I am volunteering with my department at my university (unpaid), am I allowed to travel overseas without any problems with an official letter from my advisor (my employer), knowing that I have a valid F-1 Visa Stamp on my passport till the end of 2014?
1 Answer from Attorneys
As long as the F-1 visa in your passport, issued by the U.S. Consulate, is still valid & will still be valid beyond your intended return date to the U.S., then you should be re-admitted without incident. If not, you might need to obtain a new visa at the U.S. Consulate while abroad. CBP will not admit you without a valid visa, which is entirely different than an admission stamp in one's passport.