I just realized that my return ticket is 90 days after arrival while the permit to stay is 90 days counting arrival day. Technically, I'll be in an overstay situation for a few hours the day of my departure. What is the best way to solve this?

1. Risk it and pay the fine on departure (100 THB for one day?)(impact on future visa application?)

2. Go to immigration for an extension (isn't that 1900 THB even for one day?)(what do I need?)

3. Take a quick trip over the boarder in the last month and come back with a 30 day no-visa stamp? (cost depends on the trip of course but will be higher than the first two solutions anyway)

4. Changing return day (no flight available so far in my fare class or much much more than solutions 1-3 above)

Specifics: USA passport, 90-day single entry visa O-A based on visiting Thai family.

Suggestions welcome.

Overstay is charged at 500 baht a day (max 20k), but is not collected by immigration if overstay is 1 day only and are leaving by air. You will get a small blue overstay stamp placed in your passport, but it will not affect future entry into the Kingdom or the ability to obtain a new visa. You just need to be careful not to get caught up in a police check on the way to the airport, albeit small. Maybe leave a little extra time to arrive at the airport before your permission to stay expires, as sounds like an early morning flight. After check-in go to the normal immigration desk, the officer will notice you are on overstay and you will be directed to a different officer to pay the fine and get stamped out of the country. Your visa will have been Non-O with a 90 day permission to stay. Non O-A visa is a long stay (retirement) visa giving 12 months permission to stay on entry.