How often do I need to inform immigration about my stay on an OA visa in Thailand?

You need to go to the immigration office on Tuesday and see how you can file a TM30 (foreigner in residence) form. You might be able to do it with just your lease OR you might need documentation form your landlord I don't know.

That's why I said go to the immigration office and see how you can file a TM30. You WILL need to have that receipt of having done one at some point so get it out of the way, Most offices fine people 800baht for not filing a TM30 within 24 hours of coming into the country, so the worst you're looking at is an 800baht fine.

@Carl **********

, that TM6 is an arrival/departure card, given to you when you arrive, they take the arrival part of it and you have the matching "departure card" piece in your passport.

As I said, when you arrived you or your land lord should have went to the immigration office and filed a TM30 (that's the form that says a foreigner is staying at xxx residence). You file a new TM30 with the immigration office every time you come back into the country (although some offices want you to file a new one every time you come back in to the province, so check with YOUR immigration office.

Another things (totally unrelated) is 90 day reporting. You do that when you have been in thailand 89 days from the date you stamped in.

As I said, you can do a 90 day report 15 days before down until 7 days after your actual due date.

The only time you don't do a 90 day report is if you leave the country before the 90 day due date. Then the count down resets when you stamp back in and your next 90 day report is due 89 days from the date you stamped back into the country.

90 day reporting is free and you do it at the immigration office in your area where you live. Once you do one in person (to get into the 90 day data base) you should able to use the online system for your future 90 day reports

@Carl **********

oaky you're confusing a couple things

Once you get here IN thailand you or your land lord needs to go file a TM30 form within 24 hours of you getting here. It has NOTHING to do with the TM6 arrival card you filled out (that card is meaningless so get that out of your head).

THEN

If you are inside thailand on the 90th day you need to go file a 90 day report at your immigration office. You can do this from 15 days before down until 7 days AFTER your actual 90th day, BUT you need to do this. The only time you are not obligated to file a 90 day report is if you leave the country BEFORE the 90 days runs out. Then when you come back your next 90 day report is due 90days later.

You mean a 90 day report? You should do a 90 day report every 90 days (if you have been in Thailand for 90 days or thereabouts).