A Singaporean expert in Vietnam usually falls into one of two patterns: seconded by the Singapore parent for a short project, or hired directly by the Vietnamese company. The tax outcome differs sharply, because the Vietnam–Singapore double tax treaty (signed 1994, in force) only shelters employment income while the individual is not a Vietnamese tax resident and the pay is not borne by a Vietnamese permanent establishment. This article covers only the Singapore branch; Chinese experts are dealt with in a separate live article on residency and the 183-day rule, and Indian IT experts in the companion article in this cluster — three different treaties, three different answers.
Legal basis and analysis
Residency comes first: presence of 183 days or more in a calendar year or a continuous 12-month period, or a habitual abode, makes the individual a resident who must declare worldwide income under the progressive scale of Personal Income Tax Law 109/2025/QH15 (15th National Assembly, passed in 2025).
The treaty 183-day test is not the domestic one: under the employment article of the Vietnam–Singapore treaty Vietnam may tax if presence exceeds 183 days in the relevant 12-month period, or the employer is Vietnamese-resident, or a Vietnamese permanent establishment bears the cost — failure of any single limb removes the treaty shelter.
Treaty relief is procedural: a Singapore certificate of residence and the treaty-notification file must be in place before finalisation; without them the Vietnamese authority applies domestic law first and any refund is argued afterwards.
Frequently asked questions
Where does a Singaporean working in Vietnam pay taxes?
Tax is paid where the treaty and domestic law place the taxing right: domestic law first fixes residency and source, the treaty then reallocates. An expert hired by the Vietnamese company is withheld on in Vietnam monthly; a secondee paid from Singapore must still pass the treaty employment test before anyone concludes the tax belongs in Singapore.
What benefits does the Vietnam-Singapore tax treaty offer?
The main benefit is eliminating double taxation on the same employment income when all three limbs of the employment article are met, plus a foreign tax credit on finalisation for tax properly paid in the other state. The treaty also caps rates on certain passive income, but for an expert the employment article is the operative part.
Do I still have to pay tax if I stay under 183 days?
No. Staying under 183 days satisfies only one of three limbs; if a Vietnamese employer pays the salary or a Vietnamese permanent establishment bears the cost, Vietnam taxes from the first dong. Conversely, crossing 183 days makes the expert a resident who must finalise worldwide income, rather than suffer the flat 20% non-resident withholding.
This article has been quality-reviewed by the FLAW AI Legal Council