Shipping goods internationally introduces a layer of pallet compliance that domestic shippers never have to think about. Most countries regulate the type of wood packaging materials (WPM) that can enter their borders, primarily to prevent the spread of invasive insects and plant diseases through untreated wood. Getting pallet compliance wrong can result in shipment rejection at the port of entry, quarantine holds, treatment costs, and delays. This guide covers the international standard that underlies most rules, the documentation that usually goes with it, and how to confirm what a specific destination requires today.
ISPM-15: The Global Standard for Wood Packaging
The International Standards for Phytosanitary Measures No. 15 (ISPM-15) is the basis for most international wood packaging regulations. Developed by the International Plant Protection Convention (IPPC) — a treaty organization under the United Nations — ISPM-15 establishes treatment and marking requirements for wood packaging materials used in international trade.
ISPM-15 requires that solid wood packaging materials (pallets, crates, dunnage) be treated to kill pests, and marked to show it. Heat treatment (HT) requires the core temperature of the wood to reach 56 degrees Celsius for a minimum of 30 continuous minutes. Methyl bromide is not generally used for new treatments, which makes heat treatment the standard in practice. Treatment is carried out by authorized treatment providers, and the mark shows who treated the wood.
Understanding the ISPM-15 Stamp
The wheat stalk logo indicates the pallet complies with international phytosanitary standards.
Two-letter country code identifying where the treatment was performed.
Unique identifier assigned to the treatment provider by the national plant protection organization.
HT = Heat Treated (the common code). MB = Methyl Bromide (restricted in many places and not generally used).
The mark should be clearly visible and legible, typically on at least two opposite sides of the pallet.
Destination Rules: Check Before You Ship
ISPM-15 provides the baseline, but individual countries may add requirements or enforce them differently, and those rules change. Instead of relying on a summary that may be out of date, confirm the current rules for your destination with your freight forwarder, customs broker, or the destination country's plant protection authority before you ship. The areas below are the ones to ask about.
Treatment and Marking
- •Confirm that the destination accepts ISPM-15 marked wood packaging
- •Confirm which treatment codes are accepted; heat treatment (HT) is the safest choice
- •Make sure the mark is complete, legible, and not painted over or partly worn away
- •Ask whether any additional marking is expected for your shipment
A complete, legible IPPC mark is the single most common thing inspectors look for.
Cleanliness and Condition
- •Wood packaging should be free of live pests, soil, seeds, and plant debris
- •Bark can be an issue; ask your supplier about debarked wood
- •Avoid pallets with visible mold, stains, or damage that could invite a closer look
- •Stricter destinations may inspect more thoroughly, so allow extra time
Clean, well-maintained pallets reduce the chance of an inspection hold.
Documentation
- •Ask whether a packing declaration is needed on the commercial invoice or as a separate document
- •Ask whether a phytosanitary certificate is required for your product category
- •Keep supplier records of treatment for your files
- •Have your customs broker review the paperwork before the shipment leaves
Requirements often depend on the product being shipped as well as the pallet.
Inspection and Enforcement
- •Inspection rates and practices differ by country and by port
- •Non-compliant shipments may be held, treated, returned, or destroyed, usually at the shipper's expense
- •Re-exported shipments generally still need compliant wood packaging
- •Cross-border truck shipments can be inspected at the border
Check the destination's current rules; do not assume last year's experience still applies.
Documentation You Need for Export Compliance
Beyond the ISPM-15 stamp on the pallets themselves, proper documentation supports smooth customs clearance and provides a paper trail in case of disputes. Here is the documentation you should maintain:
Treatment Certificate
Ask your pallet supplier what treatment documentation is available, such as the treatment provider, treatment date, and ISPM-15 compliance. Availability depends on the supplier.
Packing Declaration
Some countries ask for a packing declaration on the commercial invoice or a separate document stating that wood packaging materials comply with ISPM-15. Confirm whether your destination expects one.
Phytosanitary Certificate (if required)
Some destinations or product categories require a phytosanitary certificate issued by the exporting country's authority. Check with your freight forwarder whether your shipment requires one.
Supplier Compliance Records
Keep records from your pallet supplier confirming ISPM-15 compliance, including the treatment provider's number and the date of treatment. These records are invaluable if a shipment is questioned at the border.
Common Mistakes That Cause Shipment Delays
Even experienced exporters sometimes run into compliance issues. Here are the most common mistakes and how to avoid them:
Illegible or Missing Stamps
Inspect every pallet before loading. Marks should be clearly visible. Re-stamp or replace pallets with faded markings.
Using Non-Compliant Dunnage
Dunnage, blocking, and bracing made of solid wood must also be ISPM-15 compliant. Use plywood, OSB, or treated wood for all support materials.
Bark Remaining on Pallets
Bark on export pallets can draw attention from inspectors. Ask your supplier about debarked wood and inspect pallets before shipping.
Mixing Treated and Untreated
A single untreated pallet in a container can cause the entire shipment to be held. Verify every pallet in the load is compliant.
The simplest way to avoid export pallet issues is to source ISPM-15 compliant pallets from a supplier that can show proper markings. You can request a quote and mention that the pallets are for export; a partner supplier can tell you what heat-treated stock is available. The industry standards guide has more background on treatment and marking. Always confirm the destination country's current rules before you ship.