Foreigners is applied with the progressive tax tariff if working in Vietnam for at least 183 days

In accordance with the regulations prescribed in Point b.3, Clause 1, Article 25 of Circular No. 111/2013/TT-BTC:

b.3/ For foreigners working in Vietnam, income payers shall base themselves on the taxpayers’ working duration in Vietnam as written in contracts or documents on sending these foreigners to Vietnam to work to temporarily withhold tax according to the Partially Progressive Tax Tariff (for individuals who have worked in Vietnam for at least 183 days in a tax year) or the Whole Personal Income Tax Tariff (for individuals who have worked in Vietnam for less than 183 days in a tax year).

Therefore, foreigners are applied to the progressive tax tariff if working in Vietnam for at least 183 days.
 

The tax period for foreigners is defined in Point a, Clause 1, Article 6, the Circular No. 111/2013/TT-BTC.

For an individual who is present in Vietnam for less than 183 days in a calendar year but his/her period of presence in Vietnam is 183 days or more if counted in 12 consecutive months from the first day of his/her presence in Vietnam, the first tax period is 12 consecutive months from the first day of his/her presence in Vietnam. From the second year on, the tax year will be the calendar year.

Accordingly, for foreigners who are present in Vietnam for less than 183 days, the first tax period is 12 consecutive months from the first day.