US Tariff Math: Import or Manufacture in Thailand (2026)
Unit price gets the attention. Duty decides the outcome. For US buyers, the import-versus-manufacture choice in Thailand is usually won or lost inside the HTS code.
Why the code moves with the decision
Buying a finished stock item means you inherit the factory's design and, with it, a classification. Manufacturing to your own spec means you choose materials, assembly level and function — all of which can move the article into a different heading and a different duty rate. A stainless part shipped as a component and the same part shipped as a finished assembly rarely carry the same rate.
Get a binding ruling or a broker classification opinion before you release tooling money, not after.
Worked comparison
| Line item | Import stock goods | Manufacture to spec |
|---|---|---|
| FOB Laem Chabang / unit | USD 9.20 | USD 6.90 |
| Ocean + drayage / unit | 0.85 | 0.85 |
| Duty (assumed rate) | 3.7% = 0.34 | 5.3% = 0.37 |
| MPF + HMF | 0.04 | 0.03 |
| Tooling amortised over 10,000 | – | 2.20 |
| Landed cost / unit | 10.43 | 10.35 |
At 10,000 units the two paths are a coin flip. At 30,000 units tooling amortises to USD 0.73 and manufacturing wins by USD 1.55/unit. Volume, not ideology, is the variable.
Section 232 does not care about FTAs
If your part has meaningful steel or aluminium content, check Section 232 exposure before modelling. Material substitution during development can add or remove that duty entirely, so decide it at drawing stage.
Valuation traps when you own the tooling
Buyer-supplied tooling, moulds and free-issue materials are dutiable assists that must be added to customs value. Ignoring them is a classic post-entry audit finding. Read customs valuation and first sale and keep the tooling invoice on file per recordkeeping rules.
Where duty can come back to you
If you re-export finished goods or scrap from US production, duty drawback and FTZ options can recover a slice of the cost. Model that only if your export volume is real.
Do the arithmetic before the factory tour
Run both scenarios in our landed cost calculator, then sanity-check with the US landed cost formula. If the gap is under 8%, importing stock is almost always the lower-risk call.
FAQ
Can a design change lower my US duty rate legally?
Yes. Duty follows the article as imported, so genuine changes in material, function or assembly level can change classification. The change must be real, documented and reflected in the goods.
Who pays duty on tooling I buy in Thailand?
Tooling is usually invoiced separately, but its value must be declared as an assist to the goods it produces. Your broker adds it to customs value on the relevant entries.
Is Thailand duty-free into the US?
No. Thailand has no free trade agreement with the US, so normal MFN rates apply — but Section 301 China tariffs do not.
How accurate should my duty estimate be before tooling?
Within one percentage point. On a 30,000-unit program, a 2% classification error can erase the entire manufacturing saving.
Does first sale valuation work with Thai factories?
Sometimes, in multi-tier transactions with documented arm's-length pricing. It requires clean paperwork and broker review before you rely on it.