Mixed freight gets complicated fast. One LTL shipment, several articles, and not all of them share the same freight class. The situation changes again when those articles sit on the same pallet, skid, or handling unit.
That’s exactly what NMFC Rule 640 addresses. And under Docket 2026-2, a new density-based option is on the table for certain situations.
For shippers, the bigger question is how this changes the way mixed freight may be classified. When does density come into play, and when does the highest freight class still apply? Here’s what Item 640 is proposing and what shippers need to understand.
What is NMFC Rule 640?
NMFC Rule 640 is a National Motor Freight Classification provision that explains how mixed freight shipments are classified when a single shipment contains articles with different freight classes.
It applies when differently classified articles move in the same shipment, whether they are packaged separately or combined on the same pallet, skid, rack, platform, or other handling unit.
The rule sets the basis for how those different freight classes are assessed within one shipment. Docket 2026-2 proposes a different way to classify certain mixed freight shipments. Here’s how the current rule compares with the proposed change.
How are mixed freight shipments handled under the current NMFC Rule 640?
Under the current NMFC Rule 640, the classification depends largely on whether differently classed articles are shipped separately or combined on the same handling unit.
What happens when differently classed articles are shipped separately?
When the articles are packaged separately, each one is assessed using its own applicable freight class and weight.
So, articles moving in the same shipment do not automatically take the same freight class when they remain separately packaged.
What happens when different freight classes are combined on one pallet?
When differently classed articles are combined on the same pallet, skid, rack, platform, or package, the highest freight class generally applies.
The current rule provides an exception for properly unitized and itemized freight when the required article and weight information is provided. In those cases, the articles may still be assessed using their individual classes and actual weights.
That is the baseline Docket 2026-2 is proposing to change for certain mixed shipments.
What is Docket 2026-2 proposing to change in NMFC Rule 640?
Docket 2026-2 proposes a density-based classification option for certain mixed freight shipments under NMFC Rule 640. Instead of changing every mixed shipment, the proposal adds a new classification path when the conditions in the revised rule are met.
The table below shows the main differences between the current rule and the proposed Docket 2026-2 change.
| Area | Current NMFC Rule 640 | Docket 2026-2 proposal |
|---|---|---|
|
Differently classed freight kept separate |
Each handling unit is assessed using its applicable freight class and weight. |
Separate handling units continue to use their applicable class and weight. |
|
Different classes on one handling unit |
The highest freight class generally applies unless the current exception is met. |
Certain inspected mixed shipments may be classified using the 13-subprovision density scale. |
|
Weight and dimensions |
The current highest-class approach does not rely on handling-unit dimensions. |
If handling-unit weight and dimensions are provided on the original bill of lading, they are used to calculate density, subject to carrier verification. |
|
Missing accurate data |
Current Item 640 provisions apply. |
The carrier may use total shipment weight and overall cube or individual handling-unit weight and dimensions. |
|
Non-density factors |
The current rule generally follows the highest-class approach for mixed freight unless the exception applies. |
The carrier may still use the highest class when factors such as hazardous materials, handling, stowability, liability, packaging, or greatest dimension apply. |
So, for certain mixed shipments, the proposed rule gives the carrier another way to classify the shipment. Instead of automatically relying on the highest class on the handling unit, density may become part of the decision.
This is not the first time Item 640 has been reviewed. An earlier change proposed under Docket 2026-1 was not approved, so the current rule stayed in place. Docket 2026-2 now puts forward a different change.
When does density apply to a mixed shipment under the proposed Rule 640?
Under the proposed NMFC Rule 640, density becomes an option only after a shipment containing articles from more than one freight class is inspected.
During that inspection, the carrier looks at the freight and compares it with the information on the bill of lading. The density option comes into play if the bill of lading does not accurately describe the articles and their classes, or if articles with density-based classifications are combined within the same handling unit.
If either condition is found, the carrier has the option to classify the shipment using the NMFC 13-subprovision density scale. It is an option available to the carrier under the proposal, not an automatic change for every mixed pallet.
So, simply putting articles with different freight classes on the same pallet does not automatically make that pallet density-based. The inspection and the conditions described in the proposed rule are what bring the density option into play.
Once density is used, the weight and dimension information available for the shipment determines how that density is calculated.
How are dimensions and weight used to calculate density under the proposed NMFC Rule 640?
Under the proposed Rule 640, density is worked out using the weight and dimensions available for the shipment.
What happens when the shipper provides weight and dimensions?
If the shipper puts the weight and dimensions of each handling unit on the original bill of lading, the carrier starts with those numbers to calculate density for that handling unit. The carrier may still verify the measurements.
For a pallet, that means its weight along with its outside length, width, and height.
How is density calculated when accurate weight and dimension data is missing?
If accurate weight and dimension details are missing from the original bill of lading, the carrier still has two ways to work out the density.
It may use the shipment’s total weight together with its total cube. Or it may look at each handling unit separately and use the weight and dimensions available for each one.
Under the proposed rule, the carrier decides which approach to use.
When does the highest freight class still apply to a mixed shipment?
The highest freight class may still apply under the proposed NMFC Rule 640 when the shipment includes freight that is not classified by density alone.
The carrier reserves the right to assess the shipment at the highest classed article when:
- Not all articles in the shipment have density-based classifications.
- An article has special handling, stowability, or liability considerations.
- An article is regulated as hazardous material.
- The freight class depends on its packaging.
- The freight class depends on its greatest dimension.
- Another factor besides density determines the class.
Hazardous material is an important example. If a mixed pallet contains an article regulated as hazardous material, the carrier retains the right to use the highest classed article rather than the density-based option.
So, not every mixed pallet will be classified by density. In some cases, the highest freight class will still apply.
What does NMFC Rule 640 mean for shippers building mixed pallets?
For shippers, the proposed Rule 640 puts more attention on having the right freight information ready before the shipment moves out.
Start with knowing which articles are on each handling unit and keeping the class and weight information for those articles accurate. Where density applies, the final weight and outside dimensions of the pallet also need to be captured.
That information should make its way into the bill of lading and the shipping record instead of staying only at the packing or shipping station. Under the proposal, handling-unit weight and dimensions listed on the original bill of lading may be used for the density calculation, subject to carrier verification.
Keeping the measurement record available also gives the shipper something to refer back to if the carrier verifies the shipment later.
How does pallet dimensioning improve the Rule 640 shipping workflow?
Once a mixed pallet is complete, the shipper needs a reliable record of its final outside dimensions before it leaves the facility.
vMeasure pallet dimensioning system captures the pallet’s length, width, height, weight when integrated with a floor or platform scale, IDs, and pallet image. This gives the shipper a recorded set of measurements for the completed pallet.
In integrated workflows, vMeasure Forge, a cloud based dimensioning solution, stores the measurement record and sends the captured data to connected systems such as a WMS, TMS, or ERP. This reduces manual data entry and helps keep the same pallet information available across the shipping workflow.