Claiming USMCA preference at entry takes seconds: a code on the entry summary and a certification on file. Defending the claim can take years of distance: a verification letter from CBP or from the Mexican or Canadian customs authority, asking the importer to prove, with the producer's records, that the goods actually originated. Preference saves real money at entry. The file behind it decides whether you keep the savings.
What originating actually requires
Goods qualify by meeting the rule of origin for their classification: a tariff shift, a regional value content threshold, or both, calculated under the agreement's rules, including de minimis and accumulation provisions where they apply. Qualifying is a property of how and where the product was made, not of where it shipped from. A product warehoused in Mexico from third country materials may gain nothing on its journey.
The certification of origin, which under USMCA can be completed by the importer, exporter, or producer, must contain the required data elements and cover the shipment or a blanket period. A certification copied from a supplier's letterhead with a signature, and nothing behind it, is the document equivalent of a shrug.
The records behind the certification
The defensible file holds the producer's bill of material with origin of components, production records, the rule of origin analysis showing the shift or value calculation, and supplier declarations for materials claimed as originating. Importers who claim on the basis of a producer's certification should obtain the supporting analysis at onboarding, not after a verification letter starts a 30 day clock.
Retention runs five years from importation under USMCA record rules, matching the window in which verification can reach back. Brokers holding documents do not reduce the importer's duty to produce them. If the producer goes out of business in year three, the file you collected in year zero is the whole defence.
What a verification looks like
CBP verifies through written questionnaires to the importer, and the exporting country's authority can visit the producer. The questions are specific: bills of material, costs, production locations, inventory methods for fungible materials. Extensions exist but are not guaranteed, and a claim that cannot be substantiated is denied, with duties, and potentially penalties where the claim was careless, assessed retroactively across the blanket period's entries, not just the one sampled.
One failed verification therefore prices itself across every entry that relied on the same certification. That multiplication is why preference files deserve audit treatment proportional to the duty saved, and why a sample self check each year, pulling one product's full origin file and reading it cold, is worth more than a binder nobody opens.
When to stop claiming
A claim should pause when the evidence does: a supplier change without a new analysis, a component sourced from a new country, a producer who stops answering questions. Entering at the MFN rate while the file is rebuilt costs a known, bounded amount. Continuing to claim on a broken file risks the unbounded version. Confirm the current rule and any product specific requirements with a licensed customs broker before changing a claim, and document the decision either way.
Keep reading
Related guides on this site: Duty Drawback for Exporters: Recovering Duties on Goods That Leave Again Supplier Origin Declarations: What Counts as Proof When Customs Asks Answers for teams shipping Shopify orders across borders.
Frequently asked questions
What is a USMCA certification of origin?
A document containing required data elements, completed by the importer, exporter, or producer, certifying that goods meet USMCA rules of origin. It can cover a single shipment or a blanket period of up to twelve months, and it must be supportable with production and material records.
How long must USMCA records be kept?
Generally five years from the date of importation. That includes the certification and the records substantiating it, such as bills of material, origin analyses, and supplier declarations, because verifications can examine entries years after they were made.
What happens if a USMCA claim fails verification?
Preference is denied and duties are assessed on the affected entries, potentially across all entries covered by the same certification, with interest and possible penalties if the claim lacked reasonable care. That multiplication makes the supporting file as valuable as the duty saved.
Can an importer complete the certification themselves?
Yes, USMCA allows importer completed certifications, unlike the exporter only model of some agreements. Doing so responsibly requires the importer to hold the producer's origin evidence, not merely a belief that the goods are from a USMCA country.