Pallets are the unsung heroes of the supply chain. They support virtually every product that moves through a warehouse, sits on a truck, or travels in a shipping container. Yet most businesses give little thought to pallet selection — defaulting to whatever is cheapest or most available. Understanding pallet types, sizes, and materials can improve your operations, reduce damage, and even save money.
Stringer Pallets vs. Block Pallets
The two fundamental pallet designs are stringer pallets and block pallets. The difference lies in how the top deck boards are supported and how forklifts access the pallet.
Stringer Pallets
Stringer pallets use two or three parallel boards (called stringers) running between the top and bottom deck boards. They are very common in North America. Standard stringer pallets are accessible from two sides by a forklift, though notched stringers allow partial four-way entry.
- Often the most affordable wood pallet design
- Two-way or partial four-way entry
- Widely available in standard GMA (48x40) and other sizes
- Easy to repair, since damaged boards can be replaced individually
- Best for: General warehousing, domestic shipping, single-use applications
Block Pallets
Block pallets use solid blocks of wood (typically nine blocks) positioned between the top and bottom deck boards. This design allows true four-way forklift access from any side, making them more versatile in tight warehouse spaces. Block pallets are common in Europe and are also used in the United States.
- Usually more expensive than stringer pallets
- True four-way entry for forklifts and pallet jacks
- Often stronger and more durable than stringer pallets of equal size
- Often preferred for automated warehouse systems
- Best for: International shipping, automated warehouses, heavy loads, repeated use
Pallet Materials: Wood, Plastic, and Metal
While wood dominates the pallet market, plastic and metal pallets have carved out important niches. Each material offers distinct advantages depending on your application, industry, and supply chain requirements.
Wood Pallets
Wood is the most common pallet material. Wood pallets are widely available, easy to repair, and widely recyclable. Their primary drawbacks are susceptibility to moisture, pest infestation (requiring ISPM 15 treatment for international shipping), and inconsistent quality in used markets.
Plastic Pallets
Plastic pallets are lighter than many wood alternatives, easier to clean, and resistant to moisture and pests. They are often chosen where hygiene is a concern. The higher upfront cost can be offset by a longer lifespan, and plastic pallets do not need ISPM 15 treatment for international shipping.
Metal Pallets
Metal pallets, typically steel or aluminum, offer high load capacity and durability. They are used in heavy industrial applications. Metal pallets cost more than wood or plastic but can last a long time with proper care.
Standard Pallet Sizes
Pallet sizes vary by region and industry. Using the correct size ensures compatibility with your warehouse racking, transport vehicles, and international shipping requirements.
- 48 x 40 inches (GMA): The North American standard, used by grocery, retail, and general manufacturing
- 42 x 42 inches: Common in paint, telecommunications, and chemical industries
- 48 x 48 inches: Popular in oil, drum, and barrel shipping
- 1200 x 800 mm (EUR pallet): The most common pallet size in Europe
- 1100 x 1100 mm (Asia): Standard in Japan, South Korea, and parts of Southeast Asia
ISPM-15 Compliance for International Shipping
The International Standard for Phytosanitary Measures No. 15 (ISPM 15) requires that solid wood packaging materials used in international trade be treated to prevent the spread of invasive insects and plant diseases. This applies to wood pallets, crates, and dunnage. Rules can vary by country, so check current regulations for your destination.
Treatment Options
- Heat treatment (HT): Wood is heated to a core temperature of 56 degrees Celsius for at least 30 minutes
- Methyl bromide fumigation (MB): Being phased out in many countries due to ozone depletion concerns
- Dielectric heating (DH): Uses microwave or radio frequency energy to achieve required temperatures
- All treated pallets must display the IPPC/ISPM-15 stamp with treatment code and country of origin
Non-compliance with ISPM 15 can result in shipment delays, forced treatment at destination, or even rejection and return of goods. Always verify that your wood pallets carry the proper ISPM 15 stamp before loading international shipments.
How to Choose the Right Pallet
Selecting the optimal pallet requires balancing cost, performance, and application requirements. Consider the following factors when making your decision.
- Load weight: Ensure the pallet's dynamic and static load ratings exceed your requirements
- Warehouse system: Automated systems often require block pallets with precise dimensions
- Shipping destination: International shipments require ISPM 15 treated wood or non-wood alternatives
- Hygiene requirements: Some applications call for plastic pallets, so check what applies to you
- Single-use vs. multi-trip: Wood stringers are often the cheapest for one-way shipments; block or plastic pallets for multi-trip
- Racking compatibility: Verify your pallet dimensions work with your existing racking system
Industry-Specific Recommendations
Hygiene-Sensitive Goods
If you ship food or other hygiene-sensitive products, check current regulations and your customer's requirements before choosing a pallet. Plastic pallets are easier to clean. If using wood, ensure pallets are clean, dry, and free of visible mold or contamination.
Manufacturing and Automotive
Heavy-duty block pallets (wood or metal) are often preferred for their load capacity and four-way access. Some automotive supply chains use returnable plastic pallets in closed-loop systems to reduce waste and keep pallets consistent.
E-Commerce and Retail
Standard GMA wood stringer pallets are a common, cost-effective choice for domestic retail distribution. For retail display applications, consider half-pallets (24x40 inches) that fit directly into store aisles and reduce handling labor.
No matter your industry, the right pallet is the one that safely supports your product, fits your logistics infrastructure, and delivers the best total cost of ownership over its useful life.
New vs. Used Pallets
Used pallets usually cost less than new and suit many applications. The used pallet market commonly grades pallets by condition, much like used boxes, though definitions vary by supplier. Grade A used pallets typically have minimal wear. Grade B pallets may have cosmetic damage or minor repairs. When buying used, inspect for broken boards, protruding nails, and signs of pest damage.
For businesses that consume pallets in high volume, a pallet recycling or return program can reduce costs. Some pallet pooling companies offer rental programs where you pay per trip rather than purchasing pallets outright, which is worth comparing if your shipping volumes are predictable.
Pallet Maintenance and Inspection
Regular pallet inspection prevents accidents and product damage. Before loading, check for cracked or broken boards, loose nails or fasteners, signs of mold or moisture damage, and any structural weakness that could cause failure under load. Remove damaged pallets from service immediately, because a pallet failure can damage product and injure workers.