• For land border entries: limited to two visa-exempt entries per calendar year. 
• For air arrivals, the situation is more ambiguous. Some sources used to say “unlimited entries by air,” but newer reports claim there is a practical limit of 2 per calendar year by air, and a 3rd could be denied. 
• According to Thai legal-immigration media, “travellers who attempt more than two visa-exempt entries within a year may be denied entry on their third attempt.”
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