A tariff shift is a rules-of-origin test used in free trade agreements — most notably USMCA — to determine whether a product qualifies for preferential duty treatment. It requires that non-originating materials (materials sourced from outside the FTA territory) undergo a specified change in Harmonized Tariff Schedule classification during manufacturing within the FTA territory. If the required tariff shift occurs, the finished product qualifies as originating and may receive a reduced or zero duty rate.
Why It Matters for Importers
Tariff shift rules are the most common method used in trade agreements to verify that real manufacturing — not just packaging or minor processing — occurred in the FTA territory. If your product uses materials from outside North America but is manufactured in Mexico or Canada, you can still claim USMCA preferential treatment if the non-originating materials undergo the required change in HTS classification.
However, the required shift varies by product. Some products require a change at the chapter level (first two digits of the HTS code), while others require a change only at the heading level (first four digits) or subheading level (first six digits). Using the wrong standard or failing to document the shift properly can result in denial of the preferential claim and retroactive assessment of full duties.
Types of Tariff Shifts
- Change of Chapter (CC): The non-originating material must shift from one HTS chapter to a different chapter. This is the most stringent test.
- Change of Tariff Heading (CTH): The material must shift from one four-digit heading to a different heading, though it may stay within the same chapter.
- Change of Tariff Subheading (CTSH): The material must shift from one six-digit subheading to a different subheading, though it may stay within the same heading. This is the least stringent test.
Documentation Requirements
To claim USMCA treatment based on a tariff shift, you must document the HTS classification of each non-originating material before manufacturing and the classification of the finished product after manufacturing. This requires a bill of materials (BOM) that identifies each component, its origin, and its HTS classification. The producer or exporter must provide a USMCA certificate of origin supporting the tariff shift claim.
For a detailed guide to USMCA qualification methods including tariff shift analysis, see our USMCA rules of origin guide.