If you stay longer than 30 days uninterrupted in Thailand you will
need a visa. There are tourist visas or
non-immigrant visas for a longer stay.
The tourist visa is good for 60
days each entry. You can get more than one entry.
Each entry with the non-immigrant visa
allows you to stay 90 days. You can get
more than one entry. You can get the non-immigrant
visa with multiple entries. Than you are allowed to leave and
enter the Kingdom of Thailand as often you want within one year. But even with this visa
you have to leave Thailand every 90 days.
You can also do some visa run with the 'visa on arrival'.
You have to leave Thailand after your visa expires and re-enter Thailand
immediately. On leaving Thailand you will get a departure stamp and
after re-entering you will get a new visa for Thailand. But the visa duration differs by the way how you enter Thailand. If you enter the Kindom of Thailand by land form a bordering country, you will get a 15-days visa on arrival. If you enter Thailand on an internatinal airport, you will get a 30-days visa on arrival. You can repeat this as often as you want.
