I hope someone has some insight into this with respect to how the Thai immigration system works regarding the 30 day entry stamp rules. As I understand the rules, one can enter and leave Thailand on 30 day entry stamps for up to 90 days (spent in Thailand) within a 180 day period.

Assuming that is still true, here is my hypothetical question: If one were to have 2 valid passports issued by the same country (lets say the US for example, where in some cases this is possible), each with a different passport number, but with the same name of the owner in both, could one come into and out of Thailand on the first passport for the first 90 days, and then use the second passport to come and go for the next 90 days? And then revert back to the first passport for the following 90 days and so on.

In other words, does Thai immigration keep track of you by your passport number, or by your name? I have to think they use the passport number as many people can have the same names.

Part of the question would be what about if one had 2 passports from two different countries? I imagine that would be simpler.

You are wrong as there has been no such 90/180 day requirement for several years.

As for dual passports have seen reports here of immigration pointing out both on there computers.

Also, information recorded on immigration computers is:

Passport Number;

Full Name;

Date of Birth.

So long as two out of the three do not match up, it's accepted it's a different person.

That is, passport number and one of the other items, I meant to say.

Means people with the same name do not, usually, get 'linked'.

Embedded chips with biodata give added security on identity.

Edited December 3, 201114 yr by Ginkas

So then how many times can you come in and out on a 30 day entry stamp? Is there a limit to it?

There is no limit as long as for tourist reasons.

^^ Note: You only will get 30 days Entry Stamp, when arriving by Air. When arriving through a land border, you only will get 15 days.

Edited December 3, 201114 yr by MJCM