Calculate harmonized tariff duty using a preferential trade agreement rate instead of MFN rate
domain: hts.usitc.gov · 6 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Confirm the country of origin of the goods qualifies for a specific preferential trade agreement (e.g., USMCA, KORUS, GSP where applicable)
Locate the special duty rate column for the applicable trade agreement in the HTS schedule for the relevant subheading
Verify that a valid certificate or proof of origin is in hand before claiming the preferential rate at entry
Calculate the duty amount using the preferential rate applied to the customs value
Declare the correct special program indicator on the entry summary to trigger preferential rate treatment in the customs system
Retain origin documentation for the record-keeping period required by the applicable agreement in case of a CBP audit or verification
Known gotchas
Claiming a preferential rate without a valid supporting origin certification exposes the importer to back-duty assessments at the MFN rate plus interest if CBP audits the entry
Not every HTS subheading has a preferential rate under every agreement; a free or reduced rate must be confirmed in the HTS schedule for the specific agreement, not assumed
Generalized System of Preferences (GSP) benefits have been subject to periodic expiration and reauthorization; always confirm GSP is active for the product and country before claiming it
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