According to the ;

The TM30 notification and its underlying laws are about the obligation of a landlord (housemaster, possessor, or manager) to report the stay of a foreigner (non-Thai national) in his/her property...the government has started to enforce it...and added this as a requirement to the 90-day reporting and extension of visa.

Section 37 of the Immigration Act, B.E. 2522 (1979) also stipulates that a foreigner residing in Thailand should notify the police station if he/she visits another province for more than 24 hours from the time of arrival. This would mean that a short weekend trip from Bangkok to Phuket would cause more red tape, even when you have already done all the basic TM30 reporting.

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