Can foreigners with a marriage visa use it to apply for a job in Vietnam or do they have to re-register for a work visa?
In this case, you cannot use a marriage visa to apply for a job in Vietnam.
Based on Article 8 of the Law on Entry, Exit, Transit, and Residence of Foreigners in Vietnam 2014 modified by Point d, Clause 3, Article 1 of the Law on Entry, Exit, Transit, and Residence of Foreigners in Vietnam, amended 2019 stipulates:
Visa symbol
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16. LĐ1 - Issued to foreigners working in Vietnam with confirmation that they are not subject to a work permit, unless an international treaty to which Vietnam is a member has other provisions.
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18. TT - Issued to foreigners who are spouses and children under 18 years old of foreigners who are granted visas with symbols LV1, LV2, LS, DT1, DT2, DT3, NN1, NN2, DH, PV1, LD1, LĐ2 or foreigner is the father, mother, wife, husband, or children of Vietnamese citizens.
According to Article 7 of the Law on Entry, Exit, Transit, and Residence of Foreigners in Vietnam modified by Clause 2, Article 1, Law on Entry, Exit, Transit, and Residence of Foreigners in Vietnam, amended 2019 There are regulations on the validity and form of visas as follows:
Validity and form of visa
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3. Visa is valid once or multiple times; Electronic visas and visas issued for the cases specified in Point b, Clause 2 of this Article are valid once.
According to the above regulations, each type of visa will have a different purpose and the purpose of that visa cannot be changed. TT visas are issued to foreigners entering Vietnam to get married and LD visas are issued to people entering Vietnam to work.