Can I extend my stay in Samui for 30 days and how many times can I do this?

In Samui, you can apply for a 30-day extension of stay at the immigration office; however, it's often suggested to wait until you have about two weeks left on your initial stay. The extension can only be applied for once per entry, meaning if you need to stay longer after that, you'll have to exit the country and re-enter with a new visa or under a visa exemption.