Do unvaccinated travelers to Thailand still have to quarantine?

From the official Thai pronouncenent:

“Likewise, unvaccinated/not fully vaccinated travellers who have proof of a negative result from an RT-PCR test or professional ATK within 72 hours of travel will be allowed entry and are free to go anywhere in the kingdom.

The unvaccinated/not fully vaccinated travellers without a negative test result within 72 hours of travel are required to follow the public health instructions and guidelines as deemed appropriate by the Health Control officer at the point of arrival. All expenses incurred will be the responsibility of the travellers.”

Please note this last sentence. Unvaccinated travelers with no negative test within 72 hours are essentially at the mercy of the whims of the individual Health Control Officer who can make you do whatever he or she deems appropriate at the moment, and any and all associated expenses must be paid by you. Not a small thing.

0 days. Just a PCR.

no quarantine , Just test

No quarantine requirements anymore, but if unvaccinated you’ll need a PCR or ATK with certificate from a authorised medical facility issued 72 hours prior to departure. Theory says that if you don’t have one you go through screening tests on arrival, but I believe you’ll have issues boarding your plane if you don’t have one.

I don't believe quarantine is an option anymore.

It's either show your proof of vaccine at checkin, or show a certificate of negative covid test results from a test taken within 72 hours of your departure.