Here is some information. If you have no other income and you didn’t bring money into Thailand the you could file a return and get the tax back. The personal tax exemption is 150,000 baht. Even if you brought money into Thailand you should be ok if the total is less than the 150,000. There are some other exemptions which may raise the amount. I am not a tax accountant. I’m going by what I see online and then information provided by my tax accountant here in Thailand. I’ve filed a Thai tax return the last 2 years and with the exemptions and tax treaties between the US and Thailand I did not have to pay any tax here. I don’t know how long it takes to get a refund but next year I expect to,get one.