CIRCULAR IAF® 05/26 - MEXICAN CUSTOMS LAW REFORM: UNDERVALUATION, PRECAUTIONARY SEIZURE AND CUSTOMS VALUATION

1. Valuation differences and precautionary seizure

What does this mean?

The 50% or greater valuation-difference threshold is eliminated. Where the new grounds for precautionary seizure apply to specific goods, a declared value below the transaction value of identical or similar goods may trigger a precautionary seizure. 

The Second Transitory Provision authorizes the customs authorities to determine the goods and procedures subject to this rule and, for other goods, the percentage difference that will apply.

Example. A company imports 5,000 units at USD 8.50 per unit, while the customs authority identifies a transaction it considers comparable at USD 10.00 per unit. The difference is 15%. If the goods fall within a category for which the authority applies the seizure provision without a percentage threshold, the goods may be seized even if the company subsequently demonstrates that USD 8.50 was a properly determined customs value.

Recommendation. Adopt a preventive approach. Any material difference compared with comparable transactions should be capable of being explained before customs clearance. Companies should not wait until a PAMA is initiated to compile the supporting documentation substantiating the declared customs value.

Legal basis: Articles 144, Section XII, second paragraph; 151, Section VII; 153, second paragraph; and the Second Transitory Provision.

2. Substitution of the precautionary seizure

What does this mean?

The precautionary seizure may be substituted to obtain the release of the goods by providing a deposit covering the applicable taxes and, where applicable, countervailing duties associated with the valuation difference determined by the authority. For goods not subject to estimated prices, the reform establishes two scenarios:

1. Where the valuation difference is less than 20%, substitution may be requested through a cash deposit or a customs guarantee account.

2. Where the valuation difference is 20% or more, substitution is limited to a cash deposit, subject to the applicable legal requirements.

Example. If a customs value of USD 100,000 is declared and the authority determines a reference value of USD 130,000, the difference is 30%. In addition to defending the declared value, the company should consider the liquidity impact of making the deposit required to obtain the release of the goods.

Recommendation. Identify critical shipments and assess in advance the potential financial impact of a valuation difference, particularly for high-value goods or goods that are essential to production.

Legal basis: Article 154, second paragraph, Sections I and II.

3. Customs regimes that defer the payment of duties and taxes

What does this refer to?

Transactions under customs regimes in which duties and taxes may be assessed without being paid at the time of importation, including certain IMMEX temporary imports, the bonded warehouse regime, the Strategic Bonded Facility regime, and other customs regimes covered by the Customs Law.

What changes?

Article 177, Section XII reduces from 50% to 20% the valuation difference that may give rise to a presumption of an infringement, provided that, had the goods been imported definitively, the difference would also have resulted in the total or partial underpayment of import duties or countervailing duties.

Example. An IMMEX company declares a value of USD 80,000 and the authority determines a reference value of USD 100,000. The difference is 20%. If, in a definitive importation, that difference would have resulted in an underpayment of IGI or countervailing duties, the statutory presumption of an infringement may apply. 

The valuation difference alone is not sufficient; all elements required under the applicable provision must be met.

Recommendation. IMMEX companies should prioritize the review of declared values in temporary import transactions, particularly in consignment transactions, related-party transactions, or transactions involving values that differ materially from those reported in other imports.

Legal basis: Article 177, Section XII.

4. The reform does not change the customs valuation methods

The reform does not replace the statutory methods for determining customs value.

Customs value continues to be determined in accordance with Articles 64 through 78 of the Customs Law. This is particularly relevant in two common types of transactions:

Consignment transactions or transactions without a sale: 

Where there is no sale for export to Mexico, the transaction value method under Article 64 cannot automatically be used. The valuation methods provided under Article 71 must instead be applied successively, and the basis for the declared value must be properly documented.

Related-party transactions: 

The transaction value may be accepted only where the relationship between the parties did not influence the price. The company should maintain sufficient documentation to demonstrate how the price was established, as well as all direct or indirect payments associated with the goods.

Recommendation. The customs valuation file should explain not only the amount declared, but also why that amount is legally supportable. Agreements, purchase orders, equivalent documents, payment records, credit notes, dutiable additions, and the valuation methodology should all be consistent with one another.

IAF® recommendations

1. Prepare the customs valuation file before customs clearance, rather than after an issue arises.

2. Identify goods whose declared values are below those of comparable transactions and document the objective reasons for the difference.

3. Pay particular attention to consignment transactions, related-party transactions, significant discounts, royalties, tooling, engineering costs, and other indirect payments.

4. Do not automatically accept the comparable value identified by the authority. Verify that the transaction satisfies the statutory requirements for identical or similar goods, including timing, commercial level, quantity, and any applicable adjustments. The authority may lack the necessary elements to make a valid comparison or may fail to adequately substantiate the basis for such comparison.

5. Monitor the supplementary provisions that will establish the practical application of Article 151, Section VII, which must be published no later than December 31, 2026.

Conclusion

The most significant change is not that a lower price becomes unlawful, but rather that a company may first face a precautionary seizure and only afterward have the opportunity to establish that the declared customs value was correct. Accordingly, both documentary preparedness and financial planning become increasingly important.

The Decree will enter into force on January 1, 2027, pursuant to the First Transitory Provision.

Mtro. Luis Gerardo Bañuelos Hita
Director General

DOF publication:
https://dof.gob.mx/nota_detalle.php?codigo=5802077&fecha=23/10/2026#gsc.tab=0

Note: The responses, comments, and interpretations contained herein are provided solely for general guidance and should be analyzed in light of the specific circumstances of each transaction and the applicable laws and regulations in force.