A shipment can be packed, labeled, and booked correctly, then still be delayed because the pallets do not meet the destination country’s wood packaging rules. If you are asking what pallets require heat treatment, the practical answer is straightforward: solid wood pallets used in international shipments usually need to be heat treated and properly marked under ISPM 15.

The details matter because not every pallet is subject to the same rule. Domestic freight, engineered wood pallets, repaired pallets, and different destination requirements can all change what you need. Getting the pallet decision right before pickup protects your delivery schedule and prevents avoidable replacement, inspection, or re-export costs.

What pallets require heat treatment?

Heat treatment is generally required for solid wood packaging material moving across international borders. This includes wood pallets, skids, crates, boxes, dunnage, blocking, and bracing made from raw lumber. The standard most countries follow is ISPM 15, an international phytosanitary standard intended to stop insects and wood-borne pests from moving between countries.

For a typical exporter, this means a standard 48×40 wood pallet needs heat treatment when it will carry goods from one country into another. The rule applies whether the pallet is new or refurbished, provided it is made from solid wood and is part of an export shipment.

Heat treatment involves bringing the wood to a required core temperature for a defined time. The process kills regulated pests without using chemical fumigation. Once treated through an approved program, the pallet receives an IPPC mark that identifies the country, registered producer or treatment provider, and treatment method. The letters HT indicate heat treatment.

International shipments are the main trigger

A solid wood pallet used only within the United States or only within Canada does not usually need an ISPM 15 mark. Many domestic supply chains use untreated pallets because the international phytosanitary requirement does not apply to freight staying in the same country.

The requirement changes once goods cross a border. That includes full truckloads, LTL shipments, ocean containers, air cargo, rail freight, and shipments sent through freight forwarders. It also applies to the wood bracing inside a container, not only the pallets underneath the product.

Do not assume the product itself determines the requirement. A shipment of metal parts, clothing, packaged food, electronics, or machinery can all require compliant wood packaging if the goods are loaded on solid wood pallets for export.

Which pallets are exempt from heat treatment?

Not all pallet materials fall under ISPM 15. Pallets manufactured from processed wood products are generally exempt because their production process uses heat, pressure, glue, or a combination of these methods that reduces pest risk.

Common exempt materials include plywood, oriented strand board, particleboard, and other engineered wood products. Plastic pallets, metal pallets, and corrugated pallets are also outside the solid wood packaging requirement.

Wood pieces that are 6 millimeters thick or less are generally exempt as well. However, this is not a shortcut for most commercial pallets. Standard pallet deck boards, stringers, and blocks are thicker than that threshold and are treated as solid wood packaging.

An exemption can be useful for specialized export applications, but it has trade-offs. Plastic pallets may cost more upfront. Engineered wood may not offer the same strength, repairability, or load capacity as a properly built lumber pallet. The right choice depends on your load weight, storage conditions, handling equipment, destination, and shipping frequency.

The IPPC stamp is as important as the treatment

A pallet is not export-ready simply because someone says it was heat treated. For international shipment, the pallet should carry a clear, permanent, and legible IPPC mark. This mark is usually branded directly onto the wood rather than applied as a removable label.

The mark should include an IPPC symbol, a country code, a facility or producer code, and the treatment code, such as HT. Customs officials and agricultural inspectors use that mark to verify that the packaging came through an approved treatment and marking process.

A faded, partial, painted-over, or unreadable stamp can create problems. So can a pallet with a mark that appears suspicious, altered, or inconsistent with the rest of the load. Inspectors may reject the wood packaging even if the cargo is otherwise cleared for entry.

For that reason, export pallets should be checked before loading, not after the truck arrives. Confirm that the marks are visible on the pallet and that any crates, loose lumber, blocking, or dunnage also meet the destination requirement.

New, used, and refurbished pallets: what changes?

New solid wood pallets intended for export should be sourced as heat-treated and IPPC-marked from the start. This is usually the simplest option when the load is high value, time-sensitive, or moving to a market with strict inspection practices.

Used and refurbished pallets can also be suitable for export, but they require more attention. A legitimately marked pallet may remain acceptable if its construction and mark remain intact. If it has been significantly repaired, rebuilt, or remanufactured, its compliance status may change. Added replacement lumber, damaged markings, or uncertain treatment history can make the pallet a poor choice for export freight.

This is where low-cost pallets can become expensive. A reused pallet may be perfectly suitable for warehouse movement or domestic delivery, yet not be the right choice for an international order. Ask for export-grade heat-treated pallets when requesting a quote, especially if you need consistent marks, clean appearance, or a specific pallet size.

At Toronto Pallets, businesses can source heat-treated IPPC pallets alongside standard, refurbished, custom, and plastic pallet options. That makes it easier to match the pallet to the shipment instead of paying for treatment where it is not needed or risking noncompliant packaging where it is.

Heat treatment does not replace good pallet condition

ISPM 15 addresses pest-control requirements. It does not guarantee that a pallet is safe for every product or every supply chain. A heat-treated pallet can still be damaged, contaminated, structurally weak, or unsuitable for the way your freight is handled.

Before shipping, check for broken boards, protruding nails, loose blocks, excessive staining, mold, chemical odors, and damage that could affect load stability. Food, pharmaceutical, and retail shipments may require cleaner or more tightly specified pallets than industrial freight. Export compliance and product-specific packaging requirements are separate issues.

Load capacity matters as well. A pallet that works for boxed consumer goods may fail under dense machinery components, drums, stacked bags, or uneven loads. If the shipment needs oversized dimensions, extra deck boards, four-way forklift entry, or a crate built around the product, custom packaging may be the better operational choice.

How to avoid export delays caused by pallets

The safest approach is to identify the final destination before you buy or recover pallets for an order. Tell your pallet supplier where the shipment is going, whether it is leaving the country, what type of freight is being moved, and whether the load needs pallets, crates, dunnage, or all three.

Also confirm requirements with your freight forwarder, customs broker, or customer when shipping to a new market. While ISPM 15 is widely used, individual countries can enforce the standard differently or have added requirements. Your broker can advise on destination-specific documentation and entry procedures, while your pallet supplier can provide the correctly treated wood packaging.

Avoid mixing unmarked domestic pallets with marked export pallets in the same international load. It creates confusion during inspection and can lead to the entire shipment being held while the packaging is reviewed. Keep compliant pallets separated in your warehouse and make the export designation clear on purchase orders and loading instructions.

If you operate on recurring export lanes, set a standard pallet specification for each lane. That may include pallet dimensions, heat-treatment status, IPPC marking, deck configuration, load rating, and acceptable condition. A clear specification helps purchasing teams order correctly, warehouse teams load consistently, and carriers avoid last-minute changes.

Request the right pallet before the shipment is booked

For domestic freight, standard new or refurbished wood pallets are often the most cost-effective option. For international freight on solid wood, specify heat-treated, IPPC-marked pallets and include any crates or dunnage in the request. If you are unsure whether your product or destination calls for treated wood, ask before the load is built.

A quick packaging check before shipment is far easier than replacing every pallet at a terminal, port, or border inspection point. The right pallet keeps your goods moving and gives your operation one less problem to solve on shipping day.