A reminder that next Monday February 26th is a public holiday and all immigration offices around the country will be closed.
If your entry stamp falls due on the 24th, 25th or 26th then go get your extension before then. If you don’t you’ll be joining the hordes of people going on Tuesday 27th. Many immigration offices will be super busy because of the 3 day closure. You won’t get a fine because the offices were closed but you’ll still get a stamp (in Thai) that says “overstay X days. Fine waived due to closure”.
Land borders and airports are not affected by public holidays.
Plan accordingly.
TLDR : Answer Summary
Next Monday, February 26th, is a public holiday in Thailand, resulting in all immigration offices being closed. If your visa entry stamp expires on February 24th, 25th, or 26th, be sure to obtain your extension before these dates to avoid long lines on Tuesday, February 27th, when offices reopen. Although there may be a stamp indicating an overstay due to the closure, fines will not be issued. Note that land borders and airports remain operational during public holidays.