Recommendations for foreigners with Non-Immigrant Visa “O-A” (Long Stay) while staying in the Kingdom:
Upon arrival, holder of this type of visa will be permitted to stay in Thailand for 1 year from the date of first entry. During the one-year period, if he or she wishes to leave and re-enter the country, he or she is required to apply at the Immigration office for re-entry permit (single or multiple) before departure. In the case of leaving the country without a re-entry permit, the permit to stay for 1 year shall be considered void.
At the end of the 90-day stay , the foreigner must report to the immigration officer in his or her residence area and report again every 90 days during his or her stay in Thailand . The foreigner may report to the police station if there is no immigration office in his or her residence area.