Can I re-enter Thailand on a DTV visa immediately after leaving, or do I have to wait until next year?

After leaving Thailand for 180 days, you can return almost immediately. Some users suggest that you can re-enter the country as soon as one hour after exiting, and others note that returning on the same day is also feasible, particularly through air travel. However, keep in mind that land entries may have a requirement for a minimum wait of one or two days between the exit and re-entry. Your 180-day count resets upon your return.