Do foreigners holding a DTV in Thailand automatically become tax residents after 183 days?

Foreigners holding a DTV visa who stay in Thailand for more than 183 days in a calendar year do indeed become tax residents. However, their visa status does not influence this; the key factor is the duration of their stay. While tax residency typically obligates individuals to file tax returns, whether one actually must file is contingent upon individual financial circumstances, such as income sources and amounts. For example, income earned in Thailand is taxable, while foreign income may not be, depending on various factors including dual tax agreements between Thailand and the foreign individual's home country.