ISPM 15 Explained: What You Need to Know for International Shipping

If you ship goods internationally using wood pallets, ISPM 15 is not optional — it is a legal requirement in virtually every major trading nation. Yet we consistently encounter companies that either do not know about the regulation or misunderstand its requirements. This guide covers everything you need to know.

What Is ISPM 15?

ISPM 15 stands for International Standards for Phytosanitary Measures No. 15. It is a set of guidelines developed by the International Plant Protection Convention (IPPC) to prevent the international spread of wood-boring insects and plant diseases through wood packaging materials. The standard applies to all solid wood packaging used in international trade, including pallets, crates, and dunnage.

The Heat Treatment Process

The most common method of compliance is heat treatment (abbreviated HT). The process requires that the core temperature of the wood reach a minimum of 56 degrees Celsius for at least 30 continuous minutes. This temperature is sufficient to kill virtually all wood-boring organisms and their larvae.

An alternative method, methyl bromide fumigation (MB), exists but is increasingly restricted due to its ozone-depleting properties. Most developed nations have phased out or banned methyl bromide treatment, making heat treatment the de facto standard.

The ISPM 15 Stamp

Compliant pallets bear a specific stamp that includes the IPPC logo (a wheat sheaf), the country code, the producer/treatment provider number, and the treatment code (HT for heat treatment or MB for methyl bromide). This stamp must be legible on at least two opposite sides of the pallet.

• IPPC wheat sheaf symbol — verifies international recognition
• Two-letter country code (e.g., US for United States)
• Unique producer/treatment provider number assigned by NPPO
• Treatment abbreviation: HT (heat treatment) or MB (methyl bromide)
• Optional: DB marking indicating debarked wood

What Happens If You Ship Non-Compliant Pallets

The consequences are serious and immediate. Customs authorities in the destination country can reject the entire shipment at the border. The goods will be held until they are re-packaged on compliant materials, or they may be returned to the country of origin at the shipper's expense. In some cases, non-compliant shipments are fumigated or destroyed.

We had a shipment held at a European port for 17 days because two pallets in the container did not have legible ISPM 15 stamps. The storage fees alone cost us more than the entire pallet order.

How to Ensure Compliance

The simplest approach is to source all pallets for international shipments from a certified ISPM 15 treatment provider. At Commercial Pallet, every heat-treated pallet we produce is processed in our USDA-approved kilns with continuous temperature monitoring and full chain-of-custody documentation. We can provide compliance certificates for any order on request.

For companies that ship internationally on a regular basis, we recommend establishing a dedicated pool of ISPM 15 compliant pallets that are segregated from domestic stock. This eliminates the risk of accidentally loading a non-compliant pallet into an export container.