Export Pallets to the United States: NOM-144 / ISPM 15 Requirements

Moving product north looks simple until customs stops a trailer because of the pallet. The goods may be perfect, but if the wood packaging doesn't meet phytosanitary requirements, the shipment stops. In this guide we cover exactly what the United States and Canada require, how NOM-144 and ISPM 15 relate to each other, and the mistakes that cause the most holds at the border.

What phytosanitary requirements does the United States impose on pallets?

The United States regulates wood packaging material (WPM) through USDA APHIS, which oversees compliance via the American Lumber Standard Committee (ALSC) program. The core requirement is ISPM 15: all solid wood thicker than 6 mm used as a pallet, crate, box or dunnage must be:

• Debarked (bark-free, except for the small pieces the standard allows).
• Treated with heat (HT) or methyl bromide (MB) fumigation.
• Marked with the official IPPC stamp, legible and permanent.

The most common treatment is heat treatment (HT): heating the wood until it reaches a minimum of 56 °C at the core of the piece for at least 30 continuous minutes. Methyl bromide fumigation is used less and less because of its environmental restrictions.

Do pallets need ISPM 15 to enter the U.S. and Canada?

Yes, and here there is an important change many exporters still aren't aware of. For years there was a bilateral exemption that allowed wood packaging to move between the United States and Canada without ISPM 15 treatment. That exemption was eliminated: today all solid wood packaging crossing between the two countries must comply with the standard. For a Mexican exporter shipping into North America, the takeaway is simple: certified wood is no longer optional at any point in the chain.

More than 180 countries require ISPM 15, so a properly treated and marked pallet opens practically any market for you, not just the U.S. and Canada.

How does NOM-144 relate to ISPM 15 when exporting?

NOM-144-SEMARNAT-2017 is the official Mexican standard that adopts ISPM 15 and makes it mandatory within Mexico. Published in the Diario Oficial de la Federación (Mexico's federal gazette), it establishes the internationally recognized phytosanitary measures and marking requirements for wood packaging used in foreign trade.

In practice, this means that when a pallet is manufactured and marked in accordance with NOM-144 in Mexico, it automatically complies with ISPM 15 internationally. They are not two separate procedures: it is the same standard seen through the Mexican regulatory framework. For the details of the national standard, see our NOM-144 guide.

How do you read the IPPC stamp on a certified pallet?

The stamp is the first thing an inspector checks. Inside a bordered box and next to the IPPC wheat-ear symbol, it must include:

• The ISO country code: MX for Mexico.
• The unique number of the authorized producer or treatment provider.
• The treatment abbreviation: HT (heat) or MB (methyl bromide).
• For loose dunnage, the DUN code (dunnage), which is different from the one used on pallets and crates.

The stamp must appear on at least two opposite sides of the pallet and be legible and permanent. A blurred mark, one without a border or without the country code is enough for the piece to be treated as non-certified.

What mistakes cause customs to hold the shipment?

When an APHIS inspector finds non-compliant packaging, they can issue an Emergency Action Notification (EAN) and stop the load. These are the most frequent reasons:

• Pallet without a stamp ("unmarked"): the wood may have been treated, but without the mark it is considered untreated.
• Improper stamp: illegible, no border, no country code or missing the HT abbreviation.
• Wood with bark or with evidence of live pests (galleries, larvae, exit holes).
• Mixing certified pallets with untreated dunnage in the same shipment.
• Incomplete documentation: no evidence of treatment when it is requested.

The consequences are expensive: holds at the border, emergency treatment or fumigation charged to the exporter, complete repackaging, re-export or destruction of the packaging, and delays that hit your deliveries and your customer relationships.

What wood packaging is exempt from ISPM 15?

Not all wood requires treatment. Processed wood products are exempt when manufactured using heat, pressure or adhesives —plywood, OSB and particleboard— because the manufacturing process eliminates pests. The condition is that the entire package be made of exempt material. Solid wood 6 mm thick or less is also excluded.

Solid-wood export pallets and wooden crates, on the other hand, fall squarely under the standard and require HT treatment and the IPPC stamp.

How do you make sure your pallets cross without problems?

The safest way to avoid an EAN is to work with an authorized manufacturer that controls the entire process: lumber selection and debarking, heat treatment, correct marking and traceability. At BestPack Solutions we manufacture export pallets, crates and wood packaging with heat treatment (HT) compliant with NOM-144 and ISPM 15, with the correct IPPC stamp and MX code, ready to cross into the United States, Canada or any market in the world.

With a production plant in San Luis Potosí, a distribution warehouse in Saltillo, nationwide coverage and ISO 9001, 14001 and 45001 certifications, we deliver the volume and consistency you need so the pallet is never the bottleneck in your export operation.

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