To do a 90 day report by mail in Bangkok you need to postmark the envelope 14 days before the due date, and include a stamped self addressed envelope to get the receipt mailed back
Include the following in the packet:
Filled out TM47
previous 90 day report receipt
copies of:
data page of your passport
visa/extension
most recent entry stamp
TM6 departure card
TM30 receipt
Send it to THIS address just like it's written;
ATTENTION 90 Day Reporting
Immigration Office Division 1
Chalermprakiat Government Complex
120 Moo 3 Chaengwattana Road Soi 7
Thungsonghong, Laksi Bangkok
*****