Online 90 Day Reporting.
Every peson living in Thailand has to do the 90 day reporting if he/she didn't leave the country within the last 90 days.
This can be done via the following link
Click on the "Notification of staying in the Kingdom over 90 days" botton.
The reporting has to be done between 7 – 15 days before the 90 day expire date date so there is enough time to get it approved.
If the online reporting is not working or you did not get a reporting confirmation within 7 days the 90 day reporting has to be done at the immigration office in Phuket Town or Patong Beach.
Updated : November 2017