In the Special column, the duty can drop all the way to Free — but only for goods that "originate" under the trade agreement. And "originate" is a technical legal test, not "where it was assembled." Meeting it is how you actually earn the Free rate; getting it wrong means paying full duty, or worse, a penalty for a bad claim. Here's how the rules of origin work.
First, a distinction that trips people up: there are two kinds of origin. Non-preferential origin — decided by the substantial transformation test — is what sets your "Made in" marking and whether Section 301 or Column 2 applies. Preferential origin, the subject of this article, is a separate and stricter set of rules that decides whether you qualify for a free trade agreement's duty break. A product can be "from Mexico" for marking and still fail to qualify for the USMCA rate.
Three Ways a Good Can "Originate"
Under a modern agreement like the USMCA (United States–Mexico–Canada Agreement), a good originates if it is one of:
- Wholly obtained. Entirely grown, mined, or made in the region — crops harvested in Mexico, minerals extracted in Canada. These qualify automatically.
- Made entirely from originating materials. Every input already qualifies, so the finished good does too.
- Made with non-originating materials that meet the product-specific rule. This is the real-world case for most manufactured goods — and it's where the tariff shift and regional value content come in.
The Tariff Shift: A Change in Classification
The most common rule of origin is a tariff shift (a "change in tariff classification"). It says: any non-originating material has to undergo a specified change in its HTS classification as a result of processing in the region. In plain terms — the parts come in under one HTS code and the finished good leaves under a different one. That change is the evidence that real transformation happened.
Because the rule keys off the HTS code, this is where reading the code earns its keep. It's also why assembly often isn't enough: if your imported parts and your finished product fall under the same heading, no shift has occurred — and simply screwing together non-originating components in Mexico won't make the good originate.
Regional Value Content: Enough Local Value
Some product-specific rules require — instead of, or on top of, a tariff shift — a minimum regional value content (RVC): a set percentage of the good's value has to come from the region. USMCA gives you two ways to calculate it, and you generally choose whichever helps:
- Transaction value method — regional content of at least 60% of the good's value.
- Net cost method — at least 50%.
Some sectors are stricter: passenger vehicles, for instance, must hit 75% RVC. And there's a safety valve — under the de minimis rule, non-originating materials that fail the tariff shift can be disregarded as long as they're no more than 10% of the good's value.
The Certification Is a Claim, Not Proof
Under USMCA there's no government form — you make a certification of origin containing nine required data elements, and it can be completed by the importer, exporter, or producer. You keep the supporting records for five years.
Here's the part importers underestimate: the certification only asserts that the good qualifies — it doesn't make it qualify. If the product actually fails the tariff shift or the RVC threshold, Customs can reject the claim no matter how clean the paperwork looks, bill you the duty you skipped, and add penalties for a false claim. Certify only what you can actually prove.
Where to Find the Rule for Your Product
Every product has its own rule of origin, keyed to its HTS code and listed in the agreement's annex. For USMCA, those product-specific rules live in the HTS's General Note 11. Find your HTS classification, look up its rule there, and you'll see exactly what it takes — a tariff shift, an RVC threshold, or both.
Verify this with your customs broker. Rules of origin are technical and product-specific, and under “reasonable care” a wrong claim is your liability as the importer — not the factory's or the forwarder's. Use this to understand how qualification works; confirm your product's specific rule, your calculation, and your certification with a licensed customs broker or trade counsel before you claim the rate.
The Bottom Line
The Special column shows you a Free rate; the rules of origin decide whether it's yours. Qualifying is a specific, provable test — a tariff shift, a value threshold, or both — not a matter of where the last screw went in. Look up your product's rule, make sure you genuinely meet it, and certify only what you can defend. That's the difference between a legitimate duty-free entry and a penalty waiting to happen.
This is general guidance, not legal or customs advice. Rules of origin, thresholds, and certification requirements vary by agreement and product and change over time — confirm your specific qualification with a licensed customs broker or trade counsel before you rely on it.
Do you check the specific rule of origin before claiming an FTA rate — the tariff shift or the value threshold — or has a claim ever been rejected after the fact? We'd like to hear how you document eligibility.