How long can you stay in Thailand after your work permit and visa expire?

okay, the O/P has a yearly extension of stay from an immigration office

They DO NOT have a year-long, multi-entry Non-B visa from a thai consulate

They need to go cancel their work permit, get the termination documentation from the school, go to the immigration office where they got their extension, cancel it and then either leave the country that day OR buy the 7 days "get out of dodge" stamp for 1900baht that gives them a week to leave on

And on that note I believe the O/P knows the process now and we wish her well

IF you have the 1 year Non Immigrant B visa, which you bought at a Thai Consulate abroad, you can keep on using that Visa until the valid until date. You can even make a border run on the day before the valid until date to get a new 90 day Admitted to Stay.

BUT your work permit has to be cancelled and returned within 15 days of the last day of working at the same Ministry of Labor.

You can't stay any time at all beyond your visa expiry date unless you obtain an extension to that visa.

ok, let's clarify, do you have a visa or an extension of stay? What is your visa or extension of stay based on ? (marriage, work, etc).