I just received my new passport (old passport was about to expire).
My Thai ED visa and all of my entry and visa renewal stamps are in my old passport. My ED visa expires at the end of April, and I will be leaving Thailand then. I plan to apply for a new visa after I’ve left the country.
Do I have to transfer my ED visa and stamps to my new passport to leave Thailand at the end of April or will there be no problem leaving with my new passport and my visa and stamps still on my old passport?
TLDR : Answer Summary
You cannot transfer your ED visa from your old passport to the new one. It is recommended to carry both your new passport and your old passport, showing the visa and entry stamps in the old passport when you leave Thailand.