FAQ - Cancelling Visa & Work permit
Information from officer of the Office of Foreign Workers Administration, Department of Employment and the Immigration Bureau, say that Department of Employment doesn't have condition about the monthly salary and the people who paid. Immigration Bureau's condition for extension the foreigner's visa. The condition is the foreigner is required to earn minimum 50,000 baht as his/her monthly salary.
The revenue officer informs that the person who continually receives money from overseas as a salary for 180 days (minimum 50,000 Baht as a monthly salary) has to pay personal income tax. For more details, please access http://www.rd.go.th/publish/6045.0.html