What is the process for extending a visa exemption in Thailand?

To extend a visa exemption in Thailand, visit the immigration office in your province. Applications can be made when you have 30 days or less remaining on your stay, or 45 days in larger offices like those in Bangkok or Chiang Mai. Bring a recent photo, your passport, copies of your passport and visa, and fill out an extension form, along with a fee of 1900 baht. Alternatively, you can leave Thailand temporarily and re-enter for a new visa exemption.