Export Requirements For Mexico

Understanding Mexico’s export requirements starts with knowing which filing system applies to your shipment, not assuming one process covers every exporter. US exporters generally file through the Automated Export System (AES), while Canadian exporters use a B13 export declaration. Confusing the two is a common source of delay, and this guide helps you avoid it from the start.

AES Filing Explained for Exporters

AES filing meets export requirements for Mexico on US-origin shipments valued above the government’s reporting threshold, submitted as an Electronic Export Information (EEI) filing through the Automated Export System. That filing generates an Internal Transaction Number, or ITN, which confirms the shipment has been properly reported to US authorities. The ITN must reach the carrier before loading, since freight generally cannot move without proof of a completed filing on file.

B13 Export Declaration for Canada

Canadian exporters shipping through the US into Mexico work with a separate declaration process rather than AES, which applies specifically to US-origin shipments. The B13 export declaration serves a similar reporting function, but follows its own forms, thresholds, and submission channel distinct from the American system. Treating the two as identical creates errors, since a Canadian exporter cannot simply file through AES to satisfy their own country’s requirement.

AES Versus B13 Key Differences

AES filing and the B13 export declaration differ on a few key points:

• Filer of record: a US exporter of record for AES, a Canadian exporter of record for B13
• Filing system: each goes to a different national system, reflecting the country of origin rather than the shipment’s ultimate destination in Mexico
• Proof of filing: looks different in each case, so confirm which document a carrier or broker expects at handoff

When Each Filing Is Required

AES filing is generally required above a per-commodity value threshold, or whenever an export license applies to the shipment regardless of its declared value. Truck shipments crossing into Mexico need filing submitted shortly before the crossing itself, leaving less buffer time than ocean or air shipments typically allow. Missing that narrower window is a common cause of delay specific to ground transportation moving toward the border.

Avoiding Common AES Filing Errors

Mismatched Schedule B numbers are among the most frequent causes of a rejected AES filing, often the result of using an outdated or approximate classification. A missing ITN on the bill of lading is another common error, since carriers typically will not load freight without that confirmation number present. Late submission rounds out the leading causes, particularly for truck shipments with a comparatively short filing window.

Understanding Electronic Export Information

An Electronic Export Information (EEI) filing captures three core data points:

• The parties involved in the transaction
• A detailed commodity description
• The declared shipment value

Accuracy across each of these data points supports a correct AES filing, since errors in any one field can trigger a rejection or delay. EEI is essentially the underlying data set. AES is simply the electronic system that data gets submitted through.

Finding Your Correct Schedule B

The Schedule B number is the US Census Bureau’s own export classification system, distinct from the Harmonized System (HS) codes used for imports elsewhere. Getting the Schedule B number right is essential to a clean AES filing, since it directly determines how the shipment is classified and reported. Misclassification at this stage carries audit risk, beyond simply increasing the odds of a rejected filing at submission.

How LAC™ Supports Your Filings

Latin American Cargo (LAC™) has 25+ years of experience moving freight across the US-Mexico-Canada corridor for exporters navigating both AES and B13 obligations. Because the two systems apply to different exporters and follow different timelines, LAC’s bicultural LATAM team works with shippers on each side of the border to confirm the correct filing path before freight is booked, reducing the risk of a mismatched or missed filing at the crossing.

AES Filing Exemption Rules

Certain shipments qualify for an AES filing exemption, generally tied to value thresholds or the specific nature of the goods being exported. Exempt still means documenting why, not skipping the paperwork entirely, since an exemption statement must accompany the shipment regardless of the filing status. Assuming exemption without confirming it first can create the same delay a missing filing would otherwise cause at the border.

Record-Keeping After Filing Submission

Exporters should retain their ITN and filing confirmation alongside their shipment records, not discard them once the freight has successfully crossed the border. Customs authorities can request proof of filing well after a shipment has cleared, sometimes during an unrelated compliance review of other transactions entirely. Keeping these records organized and accessible avoids scrambling to reconstruct filing history months or years after the fact.

Filing Mistakes That Delay Trucks

Truck shipments have the shortest filing window of any transport mode, leaving little room for error when meeting export requirements for Mexico ahead of a crossing. Late or incomplete filings are a common cause of border-crossing holds specific to ground transportation, more so than ocean or air shipments with longer lead times. Submitting the filing well before the truck reaches the border protects against this particular timing risk.

Conclusion

Meeting export requirements for Mexico comes down to filing the right system for your origin country, hitting the correct deadline, and keeping accurate records. AES versus B13 is the starting distinction that determines which process actually applies to a given shipment and exporter. Getting that distinction right early prevents the errors, exemptions, and timing mistakes covered throughout this guide from ever becoming a problem.