This is the only article in the nationality series where the answer to the “treaty” part is: there is no treaty in force to apply. Vietnam and the United States signed a double taxation convention on 7 July 2015 and Vietnam completed its ratification procedures, but the United States has not ratified it following its 2017 tax reform, so the convention has never entered into force. The consequence is that US experts in Vietnam have no treaty layer of analysis, unlike Korean or Japanese experts: no residence tie-breaker, no 183-day exemption for short business trips, and the only double-tax relief sits in US domestic law. This article sets out that actual framework; readers needing a treaty in force for other nationalities should see the companion articles in this section.
1. The applicable framework: PIT Law 109/2025/QH15 alone
With no treaty, a US expert’s Vietnamese tax residence is determined entirely by Article 2 of PIT Law 109/2025/QH15: presence of 183 days or more in a calendar year or in 12 consecutive months from first arrival, or a regular place of abode in Vietnam (registered permanent residence or a home under a fixed-term lease), makes him a resident. Residents are taxed on worldwide income under the five-bracket scale in Article 9 (5%–35%), receive personal relief under Article 10 — VND 15.5 million per month for the taxpayer and VND 6.2 million per dependant — and must finalise annually in Vietnam. A short-trip expert below the residence threshold is a non-resident taxed at 20% on Vietnam-source income with no relief — and unlike Korean or Taiwanese experts, there is no treaty article to rescue that 20% withholding even for a trip of a few days.
2. The US side: worldwide filing and the foreign tax credit
US citizens are taxed by the United States on worldwide income wherever they live, so a US expert commonly owes obligations in both countries on the same salary. Because the treaty is not in force, the relief tools are unilateral US mechanisms: the Foreign Tax Credit for Vietnamese income tax paid, or the Foreign Earned Income Exclusion under US tax law if its conditions are met. These mechanisms belong to US law and the US-side file; they do not change the duty to declare and pay in Vietnam — the Vietnamese authority finalises under Vietnamese law, and the Vietnamese tax payment records are the evidence base for the expert’s US credit claim. Vietnamese employers of US experts should avoid contractual promises that “a treaty applies, so Vietnamese tax is exempt” — that commitment has no legal basis in force.
3. Documents: no treaty file, so the weight shifts to residence evidence
With no treaty-application notification procedure available, the US expert’s file is lighter on treaty papers but heavier on residence and income evidence: a presence calendar from entry–exit stamps for the 183-day test; the employment or secondment contract and complete payroll, including the US-paid portion for a resident; the Vietnamese home lease if relying on the regular-abode test; and complete Vietnamese withholding and payment records to support the US foreign tax credit. A characteristic error: the expert’s green card or complex US tax status is treated as relevant in Vietnam — it is not; the two systems are independent, and Vietnam applies its own law where no treaty coordinates them.
4. Risks, and a watch item for the future
The first risk is the “phantom treaty”: some older advisory materials still describe the 2015 convention’s clauses as if they applied, leading employers not to withhold for short trips and face back-tax assessments. The second is skipping Vietnamese annual finalisation for an expert who has become a resident, on the assumption that US withholding suffices — the two obligations are independent. The third lies ahead: the two countries are still in technical talks on a protocol amending the 2015 convention, so the position may change; when a treaty genuinely enters into force, its tie-breaker and 183-day clauses will apply only to tax periods within its scope, not retroactively. Employers with many US experts should put the treaty’s in-force status on an annual checklist rather than relying on dated advisory documents.
This article has been quality-reviewed by the FLAW AI Legal Council
