Do I need to get an extension for my tourist visa if my flight is delayed for one day?

Get the extension, keep a clean sheet as they say

Extension

@Jai ********

Don’t worry. Just bring your cancelled flight ticket and they will understand. You don’t even get fined or registered for overstay. Did the same thing Christmas time.

It depends on what your future plans are concerning Thailand. There are a few visas that will be refused if you have any overstay, even one day. If your future plans are just entering as you did before then it is of no concern, unless stopped by police for whatever reason, and not on your way to the airport, but, if in the future you want to apply for an Elite/Privilege visa you will be refused.

Pay the 500 baht for a one day overstay, or pay 1900 baht for an extension, the choice is yours.

The official answer is yes, you have to.

There's also reason to actually do so; if tomorrow by any chance you are stopped by the police, you're caught on overstay, which is not taken lightly.

Keep in mind that you don't need to accept changes by your airline if they are substantial. Not being permitted in the country during the extra day that they grant is enough reason to refuse this as a viable alternative. The airline will then have to solve it for you. The straightforward solution is to book you on a flight from one of their partners so you can leave on time.

What time tomorrow?