There are fines that can be paid upon departure but I have never heard of anyone being fined upon departure for not doing a 90 Day Report. Would be a nice little earner for them if they did.
The only fines I know people have had for not doing 90 day is when they have had to deal with the immigration office. Not at airport. Some retirees choose not to do the 90 day and pay a fine upon their yearly renewal is one example.
Morgan Bertin Majority leave Thailand and return to get the next 180 days. In theory 180 days extension available bit in practice it is not easy and some offices make it almost impossible. Depends on the office.
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