What documents are required to extend my STV in Thailand?

I don't think anyone extended their STV yet (because it's too new). I would assume it's the same as a tourist visa. You'll (probably) need:

1. Your passport and a copy of:

a. Your data ("picture") page

b. Your entry stamp

c. Your visa sticker

d. Your departure card

2. The "extension of stay request" form that you can find at your local immigration office.

3. 2x passport photos

4. 1,900 THB

*SOME* immigration offices may want a copy of the TM30 that was submitted by your landlord/ hotel. *SOME* immigration offices may want you to make an appointment.

You can get an extension of stay usually 30 days before the entry stamp expires. Some immigration offices allow up to 45 days in advance.

If you're within the time period, please let us know what documents your local immigration office requires, your nationality, and which immigration office you used.