According to Thai law, every foreigner holding a Non Immigrant visa or a retirement extension must report their current address to the closest Thai immigration office to their address when staying in the Kingdom for a period that is 90 consecutive days.
The day you receive your 90 day non-immigrant visa is officially the commencement day of your first 90 day reporting period. When the non-immigrant visa has passed its 90 day date is when the 12 month extension for the purposes of retirement comes into effect and you should do your 90 day report. Once done, your second 90 day reporting period begins.
Henceforth for as long as you legally remain in Thailand, even if you never move and still live at the same address, you must report to Thai immigration authorities every 90 days to confirm that you do still live in the same place. You should file your 90 day report at the Thai Immigration office nearest to your home address.
If you change your home address, you should report the change to immigration or the police within 24 hours using a TM.28 Form. A 90 day report can be actioned 15 days before the official due date or 7 days after the reporting date without any penalty.
There are currently four methods by which a 90 day report can be filed:
If you travel outside the Kingdom during the 90 day reporting period, the day you exit will stop the 90 day count. On the day that you re-enter Thailand, a new 90 day count will begin. You need to keep a record of the 90 day count yourself, you will not be told when you are due or excused if you forget. Immigration officials will normally impose a fine of 2000 baht for late reporting but can impose 5000 baht if they wish.