The 'Except From' Clause: Wiring Harnesses That Cannot Pass the Tariff Shift
Voltaje Integraciones S.A. de C.V. assembles automotive wiring harnesses (HS 8544.30) in Reynosa, Mexico, and ships them to a US assembly plant in Ohio. The customer requires USMCA preference on every shipment, and the ex-works price is USD 58.00 per harness. The bill of materials for one harness is: pre-terminated cable assemblies (HS 8544.42) imported from China, USD 34.00; connectors (HS 8536.69) from a Mexican moulder, USD 6.00; corrugated conduit (HS 3926.90) from the United States, USD 3.00; PVC tape (HS 3919.10) from China, USD 1.00; direct labour and factory overhead, USD 11.00; and a royalty of USD 1.50 per unit paid to a Mexican design house for the harness routing drawings. Outbound freight to Ohio is USD 2.00 per unit and is booked separately. The applicable product-specific rule is: 'A change to heading 8544 from any other heading, except from heading 8544; or RVC 50% net cost.' The company holds supplier declarations for the US conduit and the Mexican connectors only, and it has never modelled the alternative rule.
1. Does the harness satisfy the tariff-shift rule? Apply the de minimis provision and state its limits.
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No. The rule requires a change to heading 8544 from any other heading, except from heading 8544. The pre-terminated cable assembly is classified in 8544.42; that is the same heading as the finished harness. The material therefore fails the change-of-heading test by express exclusion, and the harness fails the primary rule.
De minimis does not rescue it. Under USMCA the tolerance is 10% of the transaction value of the good and applies only to non-originating materials that do not undergo the required change in tariff classification. The candidate failing materials must be identified at heading level:
- Cable assembly 8544.42, USD 34.00 - fails (same heading, expressly excluded from the rule).
- PVC tape 3919.10, USD 1.00 - a change from 3919 to 8544 is a permitted heading change, so it satisfies the rule and is not counted.
The failing material is therefore USD 34.00 against a transaction value of USD 58.00, or 58.6%. That is far above 10%, so de minimis is unavailable.
Two points are worth flagging for the file. The fact that the cable assembly is only cut to length and crimped does not matter for the tariff-shift test - classification, not processing, decides. And the origin of the connectors and conduit is irrelevant to the tariff-shift test; originating and non-originating materials are treated identically when the question is whether a classification change occurred.
2. Compute the regional value content on the net cost method and conclude whether the harness qualifies under the alternative rule.
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Net cost starts from total cost of production and removes the items listed in the definition, notably royalties, sales promotion, after-sales costs, shipping and packing, and non-allowable interest.
Total cost of production per unit: 34.00 + 6.00 + 3.00 + 1.00 + 11.00 + 1.50 royalty = USD 56.50.
Deduct the royalty: 56.50 − 1.50 = net cost USD 55.00. Outbound freight of USD 2.00 is not part of production cost and is not added; had it been booked in overhead it would have been deducted.
Value of non-originating materials: cable assembly 34.00 + PVC tape 1.00 = USD 35.00. The connectors are Mexican, and the conduit is US-origin and supported by a supplier declaration, so both are originating and excluded from the VNM. (If the conduits were merely purchased in the US from imported stock, that conclusion would change; origin follows production, not the shipping address.)
RVC = (net cost − VNM) ÷ net cost = (55.00 − 35.00) ÷ 55.00 = 20.00 ÷ 55.00 = 36.4%.
The threshold is 50% net cost. At 36.4% the harness does not qualify, and since the tariff-shift route already failed, no preference is available on the current bill of materials. The 13.6-point gap is large enough that it cannot be closed by cost reclassification; only a sourcing change will do it.
3. Recommend the most defensible remediation, and explain what changes in the supplier documentation and internal records would be needed to support it.
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The gap is driven by one line: USD 34.00 of Chinese cable assemblies that both block the tariff shift and dominate the VNM. Three routes exist, in descending order of durability.
- Move the cable assembly to originating status. Either buy pre-terminated assemblies from a US or Mexican producer that can issue a valid USMCA certification, or import bare conductor and cut, crimp and terminate it in Reynosa. In the first case the material is originating and is disregarded for the tariff-shift test entirely, and VNM collapses to about USD 1.00 - the RVC becomes roughly 98% and the good passes both routes. In the second case the input moves to a different heading, the change-of-heading rule is met, and the RVC rises because the value added in Mexico increases.
- Re-engineer the bill of materials so the harness is built from originating sub-assemblies plus a small volume of non-originating content, then re-test both the tariff shift and the RVC.
- Cost reduction alone is not a remedy; at 36.4% no plausible overhead adjustment reaches 50%.
Documentation consequences: for route 1, obtain a USMCA certification from the new cable supplier plus the underlying cost or tariff-shift worksheet, not just a signature on a form. Keep the supplier declarations for conduit and connectors current - they are the reason those values were excluded. Internally, maintain a bill-of-materials file keyed to each part number showing HS classification, origin status, value and the evidence relied on, plus a documented RVC calculation per model and per period. If the plant elects to average, record the averaging period and method in writing before the first shipment, because a method adopted after an audit begins carries little weight.