During the first two years out of a Non-Imm-O/A Longstay visa, the mandatory health insurance can be your U.S. insurance.
However, for the application to the “1-year Extension of stay Permit” before your last stay permit out of the O/A visa will expire, you need to take up one of the private Thai health insurances that are on the so called “tgia list of insurances”.
The link is below.
Your home insurance will not be accepted any more.
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