As of August 29, 2014 Immigration announced that a 30 day Exemption can be extended for another 30 days inside Thailand.
http://www.thaivisa.com/forum/topic/...ugust-29-2014/
But this assumes you have a passport from one of the eligible countries.
http://www.thaiembassy.com/thailand/...isa-exempt.php
That said, DL can be sticklers so I would recommend getting a single-entry visa from the nearest Thai Embassy/Consul. A colleague was recently denied boarding by DL in the U.S. bound for Thailand, and was forced to secure an on-ward ticket (DMK-PNH on FD for ~ 2,200 baht all in).
Having the visa overcomes a potential IDB situation. Exiting Thailand, then re-entering at a land border - either with a visa or not - should be fine, and for G7 countries/passports you'll get another 30 day exemption.
I flew FRA-BKK on TG a few weeks ago finishing a ticket and encountered significant questions when boarding. I have an Extension of Stay, and a Multiple Re-Entry Permit so a non-issue once I could figure out what they were asking about.
Originally Posted by
ghia74
I booked an open jaw on United BOS into BKK and out of SGN. I am going on Friday. I purchased tickets to fly Air Asia out of DMK to REP on Monday. I then fly REP to SGN on Wednesday via Vietnam Airlines
Is a printout of our confimation email from Air Asia and Vietnam Airlines enough evidence for United and BKK customs? I do have my my visas for Cambodia and Vietnam.
Yes. But only UA will be interested; Thai Immigration will not require proof.