I just realized my Thailand visa expires on 28 September, but my flight out is on 29 September. What would be the easiest way to get another day added? I am currently in Pattaya and will be going to Bangkok in one week.

Visit any immigration office a couple days before expiration with ticket, 1,900 baht and current 4x6cm photo to obtain a 7 day extension.

Visit any immigration office a couple days before expiration with ticket, 1,900 baht and current 4x6cm photo to obtain a 7 day extension.

That definitely is the right thing to do, but isn't it true that a 1-day overstay is a freebie? Is it a concern, for the purposes of getting a future visa, that it will count against you?

With an air exit the 500 baht fine has not been collected in the past but passport may get the overstay stamp. This is not normally a problem for entry into Thailand but some other countries don't like it (and it could change for Thailand). Although you would have to be extremely unlucky you could get stopped by police on overstay status and in that case you could be processed and meet a judge. It is especially unwise if departing from a land border as transportation to border areas is often spot checked.

With an air exit the 500 baht fine has not been collected in the past but passport may get the overstay stamp. This is not normally a problem for entry into Thailand but some other countries don't like it (and it could change for Thailand). Although you would have to be extremely unlucky you could get stopped by police on overstay status and in that case you could be processed and meet a judge. It is especially unwise if departing from a land border as transportation to border areas is often spot checked.

Thanks for the advice. Just to be sure I understand correctly: I do not have to make a quick cross border trip out of Thailand to get the extension. There is an immigration office located in Bangkok?

Yes.