Do I need to cancel my Non-B visa and work permit when changing jobs in Thailand?

When changing jobs in Thailand, you need to proactively cancel your Extension of Stay and ensure your previous employer issues a termination letter. This letter indicates your final employment date and should be taken to immigration to cancel your extension. If you cancel on your last working day, you are typically required to leave the country that same day. If you want to stay longer after your current employment ends, you could apply for a new extension, though this is often denied and you will generally receive a 7-day grace period to leave.