How to Allocate Freight Costs Across Products

A $3,000 freight invoice divided across 10 products can result in vastly different per-unit costs depending on whether you allocate by value, weight, quantity, or volume. Choose the wrong method and you'll either overprice some products or sell others at a loss.

This guide explains the four main allocation methods, when to use each one, and how to avoid the common mistakes that lead to inaccurate landed costs.

Why Allocation Method Matters

When you import multiple products in a single shipment, the freight invoice shows one total amount. But you need to know the cost per product to set accurate prices and calculate your true margins.

The challenge is that different products in the same shipment contribute differently to the total freight cost. A heavy product adds more weight. An expensive product represents more value at risk. A bulky product takes up more container space.

How you split the freight cost should reflect how each product actually contributed to that cost. If you choose the wrong method, you'll systematically miscalculate your landed costs - some products will appear more profitable than they are, while others will seem unprofitable when they're actually fine.

The Four Main Allocation Methods

There are four standard methods for allocating freight costs across products. Each has specific use cases where it produces the most accurate results.

1. Allocation by Value

How it works: Each product receives a share of freight proportional to its value relative to the total shipment value.

Example: A shipment worth $15,000 includes Product A worth $8,000 and Product B worth $7,000. On a $3,000 freight bill, Product A receives $8,000 / $15,000 x $3,000 = $1,600, and Product B receives $1,400. Allocate from the ratio, not from a rounded percentage: 53% of $3,000 is $1,600, and those missing $10 have to land somewhere.

Best for:

• Customs duty allocation - Duty is calculated on value, so allocating duty by value is logically consistent
• Insurance costs - Insurance premiums are based on declared value
• Mixed shipments with similar density - When products have roughly the same weight-to-value ratio

Not ideal when: You have a mix of expensive-light and cheap-heavy items. The expensive items absorb too much freight cost relative to their actual shipping impact.

2. Allocation by Weight

How it works: Each product receives a share of freight proportional to its weight relative to the total shipment weight.

Example: A shipment weighing 1,000kg includes Product A at 500kg (50%) and Product B at 500kg (50%). On a $3,000 freight bill, each product receives $1,500, regardless of their monetary value.

Best for:

• Sea freight (FCL) - When shipping by container, weight often determines the actual cost
• Air freight - Airlines charge primarily by weight (or volumetric weight)
• Heavy goods - Machinery, equipment, dense materials

Not ideal when: You ship bulky-but-light items. These products take up space without adding weight, so weight-based allocation understates their shipping cost.

3. Allocation by Quantity

How it works: The total freight is divided equally across all units, regardless of size, weight, or value.

Example: A shipment of 1,000 units with $3,000 freight results in $3.00 per unit, whether that unit is a $5 item or a $50 item.

Best for:

• Identical or similar products - When all items in the shipment are essentially the same size and weight
• Single-product shipments - No allocation decision needed
• Simple operations - When tracking weight and value per item isn't practical

Not ideal when: Products vary significantly in size, weight, or value. Equal allocation distorts the true cost of shipping each product type.

4. Allocation by Volume

How it works: Each product receives a share of freight proportional to its cubic volume (CBM) relative to the total shipment volume.

Example: A 20ft container (33 CBM usable) with $3,000 freight means each CBM costs about $91. A product taking 2 CBM gets $182 in freight, regardless of its weight.

Best for:

• Full container loads (FCL) - You're paying for the container space, so volume determines cost
• Bulky, low-density goods - Furniture, home decor, packaging materials
• Mixed density shipments - When some items are heavy and compact while others are light and bulky

Not ideal when: You ship LCL (less than container load), where charges are often based on chargeable weight rather than pure volume.

Same Shipment, Different Costs

To illustrate how allocation method affects landed costs, consider a shipment with two very different products:

With a $3,000 freight bill, here's how much each product would receive under different methods:

The watch's freight allocation ranges from $150 (by volume) to $1,600 (by value) - a 10x difference. Which is correct? It depends on what actually drove the freight cost.

If this was an FCL shipment where the bulky bins filled most of the container, volume-based allocation ($150 for watches, $2,850 for bins) most accurately reflects reality. If it was an air freight shipment charged by weight, weight-based allocation is appropriate.

Which Method Should You Use?

The right method depends on what's actually driving your freight costs:

Common Allocation Mistakes

These errors consistently lead to inaccurate landed costs:

1. Using the same method for everything

Allocating all costs by value is simple but wrong. Duty should be allocated by value, but freight should usually be allocated by weight or volume. Using a single method distorts your numbers.

2. Ignoring the actual billing basis

If your freight forwarder charges by CBM, allocate by volume. If they charge by kg, allocate by weight. Look at the invoice to see how you were actually charged.

3. Missing weight/volume data

You can't allocate by weight if you don't know each product's weight. Many importers default to value-based allocation because they never captured the physical data. This compromises accuracy.

4. Inconsistent methodology

If you allocate one shipment by weight and the next by value, comparing costs over time becomes meaningless. Pick appropriate methods and stick with them.

Using Mixed Allocation Methods

The most accurate approach uses different methods for different cost types. A typical mixed allocation might look like:

• Customs duty: By value (matches how duty is calculated)
• Recoverable import tax (GST, VAT, or whatever your border charges): not allocated at all. You claim it back, so it is a cash-flow cost rather than a cost of the goods, and putting it in the unit cost overstates every figure downstream. Customs duty is the opposite: nobody refunds it, so it belongs in the cost. The United States charges no recoverable import tax at the border.
• Sea freight: By volume (FCL) or by weight (LCL)
• Insurance: By value (based on insured amount)
• Broker fees: By quantity (often a flat cost per entry)
• Handling charges: By volume (relates to physical handling)

This requires more setup but produces landed costs that reflect reality. Each cost is allocated based on what actually drives that cost.

How Landara Handles Allocation

Landara makes allocation easy by letting you set the method for each cost type:

1. Upload your documents - Purchase order and freight invoices
2. AI categorises costs - Freight, duty, insurance, clearance fees are automatically identified
3. Set allocation methods - Choose by value, weight, quantity, or volume for each cost type
4. See per-unit landed costs - Instantly see how costs flow through to each product

You can adjust methods and immediately see how it affects your landed costs. This makes it easy to test different approaches and find the method that best reflects your actual cost drivers.

The right allocation method is the one that matches how your freight is actually charged. When your allocation reflects reality, your landed costs become reliable - and your pricing decisions become sound.