NMFC Freight Classes And Subclasses

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National Motor Freight Classification 

National Motor Freight Classification (NMFC) is a freight classification system created and maintained by the National Motor Freight Traffic Association (NMFTA) and used for all interstate, intrastate, and foreign commerce movement of LTL cargo. NMFC codes provide standardized freight classes meant to determine the transportability of many of the countless different commodities being shipped together in LTL shipments each year. Because LTL shipping involves a wide variety of products with different densities, liabilities, and handling considerations transported together in a single shipment, freight class codes are necessary to provide standardization so that shippers and carriers can negotiate freight rates for different types of goods.


18 Freight Classes

There are eighteen possible NMFC classifications for LTL freight, the lowest and least expensive being 50, and the highest and most expensive being 500. Freight that is dense, sturdy, and has minimal liability will be classified lower, while freight that is fragile, uniquely shaped, or prone to damage, loss, or theft will be classified higher. As a general rule of thumb, the denser a product, the lower its freight classification code. 

NMFC freight classes are usually denoted by 5-digit codes, depending on whether the item falls under a subclassification, and each NMFC code and subclass relate to a specific commodity depending on what it is, its dimensions, how it is packaged, whether it is assembled or disassembled, and the materials from which it is made. These specific codes all correspond with one of the eighteen classes of freight.

How is Freight Class Determined?

Freight class is determined based on an item’s transportability due to factors such as weight, dimension, density, storage capability, ease of handling, value, and liability from instances like theft, damage, and spoilage. The four main metrics that determine freight class are:           

Density – Density, or pounds per cubic foot, is the measurable amount of space needed for an item within a freight shipment in relation to its weight. Higher density items usually fall in a lower class, while less dense items tend to fall on the higher end of the spectrum.

Handling – Freight that requires special instructions when loaded or unloaded because of weight, shape, or other unique restrictions such as fragility, special attention, or hazardous properties that involve a higher level of care beyond the standard machines commonly used to load or unload items will result in a higher freight classification.

Stowability – Stowability refers to how your items can be transported with other commodities. Some types of freight are subject to government regulation or specific carrier policies, limiting what other types of freight with which they can be transported. Items that are hazardous, flammable, or perishable, as well as those that are particularly heavy or that protrude in an inconvenient way cannot be shipped with certain types of materials, resulting in a higher freight classification. When it comes to stowability, it is important to think about packaging. Freight that is crated or boxed to become stackable and uniform is easier and more efficient to stow in a shipment.

Liability – Liability refers to the value of a commodity and its potential to be damaged or lost in transit. Items that have a higher risk of theft, accidental damage, or may cause damage to other items during shipping will result in a higher freight class. Perishable or hazardous freight will also carry potential liability costs and concerns.


Freight Subclasses

Freight subclasses can be complex and require precision and attention to detail. Depending on the specific nature of a product, the freight class code can fall anywhere within a large range of classes and subclasses. For example, one NMFC code given for chairs/stools (82790) can range anywhere from freight class 60-400, depending on the specifics of the chair or stool in question and the subsequent subclasses for which it may qualify. If the stool or chair has a density per cubic foot of more than 30 lbs it will fall under subclass 11, giving it an NMFC code of 82790-11, a combined code and subclass that would place it under freight class 60 on the 50-500 scale. However, if the stool or chair has a density per cubic foot of less than 1 lb it will fall under subclass 1, giving it an NMFC code of 82790-1, a combined code and subclass that would place it under freight class 400 on the 50-500 scale. Because the range of freight class can vary so significantly for a single type of product depending on its specifications, it is very important to not only know the correct NMFC code for the item, but also the applicable subclass into which it fits in order to assign the correct freight class.


Calculating Freight Class for Unlisted Commodities           

The National Motor Freight Classification (NMFC) is the industry standard carriers subscribe to and use for pricing and planning LTL shipments. However, the NMFC reference guide provides the freight class and item number for many commodities but not all.

If the commodity in your LTL freight shipment is not listed within the NMFC standards, the density of the item will determine the freight class. The density of a shipment is simply its volume in cubic feet divided by its gross weight in pounds.
Learn more about the NMFC freight class and subclasses for common commodities on our freight class page.

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