Which country-of-origin question are you trying to answer?
A buyer may need a country to print on a housing, a basis for claiming USMCA preference and a decision about additional duties on the same shipment. Start by identifying the purpose of each answer. Then ask the Mexican plant for the production facts that the relevant rule needs.
Give each decision its own record
| Decision | Review basis | Evidence to request |
|---|---|---|
| Origin marking on a US import | The applicable marking rules, including Parts 134 and 102 for relevant Mexico/Canada goods and product-specific provisions | Article as imported, classification of materials and finished good, processing locations and proposed mark |
| USMCA tariff preference | HTSUS General Note 11 and the applicable product-specific rule, plus certification and other conditions | Origin criterion, BOM, input classification/origin support and any required value calculation |
| Origin for Section 301 | The origin analysis applicable to the measure, read with the relevant Chapter 99 provisions | Actual component fabrication and assembly, condition of inputs and the source of important subassemblies |
| AD/CVD coverage | The Commerce order’s written scope and applicable determinations or instructions | Product characteristics, producer/exporter, countries, process and order-specific facts |
Use the USMCA rules guide to work through preference qualification. Use AD/CVD scope preparation when a named trade-remedy order may cover the product.
A mark and a duty decision can differ
In HQ H301619, November 6, 2018, CBP considered electric motors assembled in Mexico from Chinese stator, rotor and end-cap subassemblies. The ruling found Mexico origin for marking but China origin for the Section 301 measure addressed. That historical split makes the purpose column essential. It does not decide a different motor’s treatment today.
In HQ H338716, July 21, 2025, production of a vehicle thermal management system in Mexico included molding and welding to make subassemblies. CBP separately analyzed USMCA and Section 301, finding preference eligibility subject to the applicable conditions and Mexico origin for Section 301. Neither example settles an AD/CVD scope question. Motor ruling · Thermal management ruling
Build the factory fact packet
Ask engineering and the plant to prepare a versioned record:
- Finished product, part number, drawing revision, intended use and condition at each border.
- Each material or subassembly, where it was made, its proposed classification and the evidence behind its stated origin.
- Each Mexican manufacturing step, location, equipment, inputs, intermediate output and inspection record.
- Relevant quantities, values and calculation method if the particular preference rule requires them.
- Proposed entry date, certifier or review owner, and the unresolved question for each legal purpose.
A distributor invoice can identify the seller while leaving the producer or material source unresolved. Label that gap and assign a follow-up owner. Keep customer drawings and detailed costed BOMs in the parties’ approved records.
Review changes before the next release
A substitute motor core or a move of PCBA production can affect a previous analysis. Tie the change to the first affected lot, identify the legal questions to revisit and retain the previous version. The BOM-change guide connects that task to the Mexican inventory record.
If the question is still disputed after the facts are complete, compare relevant decisions through the CBP rulings research guide and consider a prospective binding ruling with the appropriate professional. Record who made each determination and which transaction it covers.
Continue with your records
Official sources and review scope
Source check 2026-11-12. This editorial guide organizes questions and records for a Mexico–US transaction. Confirm the rules, effective dates and facts with the responsible importer and qualified professionals before filing or committing goods.