What is the TM30 process for returning to Thailand and do I need to complete it for my friend?

The TM30 is a notification of residence form that landlords in Thailand must submit to inform immigration authorities of the arrival of a foreign national at their property. As a returning resident in Chiang Mai, you can typically submit the TM30 at your local immigration office or via your landlord who is responsible for the submission. If your friend will stay at the same residence, they also need to be included in the TM30 submission.