I got my covid extension today at chaengwattana. Yes, I came here with STV visa and already extended 2 times.
No need any insurance.
Only need TM30, Recommendation lettter from the embassy, one passport photo and 1900 Bahts. That’s it.
Hope admin won’t turn off the comment session. 🙂
TLDR : Answer Summary
A user successfully obtained a COVID extension at the Chaengwattana immigration office under their STV visa, having extended it twice before. They reported that insurance was not required for this extension. Necessary documents included a TM30 form, a recommendation letter from the embassy, one passport photo, and a fee of 1900 Baht. Additional commenters pointed out that other documents, such as a passport copy, data page, visa, departure card, and entry stamp might also be required.