Bonded warehouses are legitimate and useful. They are also exactly where US authorities expect to find transshipment: goods from one country passed off as made in another to get a lower tariff. If you export to the US from or through a Vietnamese bonded warehouse, origin has to be clean on every carton.
The rule: origin is where the product was made
Vietnam has no free trade agreement with the US, so US customs applies the substantial transformation test: origin is the last country where the product became a new article with a new name, character or use. Activities allowed in a bonded warehouse never meet that test:
| Activity in the warehouse | Changes US origin? |
|---|---|
| Storage, however long | No |
| Repacking, re-palletising, splitting lots | No |
| Labelling, barcoding, adding hang tags | No |
| Combining goods from several countries in one container | No — each item keeps its own origin |
| Simple assembly from foreign parts | Usually no — and not allowed in a bonded warehouse anyway |
What the penalties look like
- US side. Under the July 2025 US–Vietnam trade framework, goods found to be transshipped through Vietnam to evade tariffs face a 40% rate instead of the normal one. The legal basis was reissued during 2026 after court rulings, so check the current status, but enforcement has not eased. Evasion cases can also bring an EAPA investigation, back duties and penalties against the importer of record.
- Vietnam side. Goods bearing false Vietnamese origin cannot be placed in a bonded warehouse, and Vietnamese customs has stepped up origin checks on exports to the US since 2025.
See US tariffs on Vietnamese goods in 2026 for current rates.
Red flags CBP looks for
- Cartons or goods relabelled shortly before export
- A "manufacturer" on the ISF or invoice that is actually a warehouse or trading company
- Exports of a product that the named Vietnamese company has no capacity to make
- Sudden shifts of a product line from China to Vietnam without a factory investment behind them
- Invoices showing one origin while marks on the goods show another
Compliance checklist for bonded shipments
- One origin per invoice line, matching the marking on goods and cartons.
- Name the real manufacturer on the ISF and invoice; show the warehouse only as stuffing location and consolidator — see ISF from a bonded warehouse.
- Keep the chain: production records, purchase documents, inbound declarations and warehouse receipts linked by lot.
- Label only with the true origin; never cover or remove existing origin marks.
- Ask for a binding ruling when a product is assembled in Vietnam from imported parts and the origin is unclear.
- Agree liability: the importer of record carries the US risk, so DDP sellers must vet suppliers whose goods go into the container.
Legitimate uses that stay compliant
Storing Vietnamese goods before export, re-exporting Cambodian goods as Cambodian (see how), and consolidating several suppliers' goods with their own origins are all lawful. The warehouse is a logistics tool, not an origin tool.