A customs guarantee account (cuenta aduanera de garantía) is a deposit with an authorized financial institution that secures the taxes a foreign trade operation could generate in Mexico. It is required mainly when you import goods declaring a value below the estimated price set by Mexico’s Ministry of Finance. It is governed by Articles 84-A and 86-A of the Customs Law.
When a customs guarantee account is required
Article 86-A, amended in the DOF on November 19, 2025 and in force since January 1, 2026, sets three cases:
| Case | What is secured |
|---|---|
| Definitive import declared below the estimated price | The tax difference. The guarantee is cancelled after 12 months unless the authority opens an audit |
| Domestic or international transit, in the cases the SAT sets | The taxes on the goods in transit |
| Strategic bonded facility (from April 1, 2026) | The applicable taxes |
A letter of credit can be used instead of the deposit. Authorized institutions are listed on the SAT portal, and the certificate details are declared on the pedimento.
When it affects imports from China
When your invoice shows a price below the estimated price for your goods, which can happen with low-cost Chinese products. Without the guarantee, clearance stops. With a real, well-documented price in your value declaration, the difference is explained and the guarantee is recovered.
The common mistake
Treating the guarantee as a sunk cost or, worse, trying to avoid it by inflating the value on paper. The guarantee is released when the value is right; an altered value is a tax problem. Plan it with your customs broker before shipping.
Importing goods with an estimated price? With OptiChina we prepare the operation so it does not stall at customs.
Sources: Customs Law (Ley Aduanera), Arts. 84-A and 86-A, as amended DOF Nov 19, 2025; 2026 General Foreign Trade Rules (RGCE), Rules 1.6.25 to 1.6.29. Current as of October 14, 2026.
