Short answer
Freight class is the NMFC rating that LTL carriers use to price a shipment. NMFTA assigns 18 classes from 50 to 500 based on density, handling, stowability, and liability. Lower classes cost less to ship. Since NMFC Docket 2025-1 took effect on July 19, 2025, density is the primary factor for many items, using a 13-step density scale.
How freight class works
The National Motor Freight Classification (NMFC) is published by the National Motor Freight Traffic Association (NMFTA). Each commodity has an NMFC item number, and the item points to a class. NMFTA says a class is set by four characteristics:
- Density: pounds per cubic foot
- Handling: how hard the freight is to move safely
- Stowability: how well it fits with other freight
- Liability: how likely it is to be damaged, stolen, or to damage other freight
Class matters mostly for LTL, because the carrier’s rate is built on class and weight. Full truckload freight is usually priced per load, so class rarely comes up.
What changed in July 2025
NMFTA’s Docket 2025-1 changes took effect on July 19, 2025. The biggest shift: many items now take their class from the shipment’s actual density on a standard 13-subprovision scale. NMFTA’s FAQ says density became the primary factor in 2025, while items with handling, stowability, or liability concerns still won’t be classed on density alone.
The older standard scale had 11 steps. The new scale added classes 55 and 50 for freight at 35 pcf and heavier. NMFTA has kept moving more items onto the same scale since then, including Docket 2026-1, effective May 23, 2026.
NMFC data now lives in ClassIT+, NMFTA’s digital classification tool, which launched in July 2025.
The NMFC 13-step density scale
For items classed by density under the standard scale.
| Density (lbs per cubic foot) | Class |
|---|---|
| Less than 1 | 400 |
| 1 but less than 2 | 300 |
| 2 but less than 4 | 250 |
| 4 but less than 6 | 175 |
| 6 but less than 8 | 125 |
| 8 but less than 10 | 100 |
| 10 but less than 12 | 92.5 |
| 12 but less than 15 | 85 |
| 15 but less than 22.5 | 70 |
| 22.5 but less than 30 | 65 |
| 30 but less than 35 | 60 |
| 35 but less than 50 | 55 |
| 50 or greater | 50 |
Source: NMFTA Disposition Bulletin 1371, Docket 2025-1, effective July 19, 2025. Check the NMFC item for your commodity before applying this scale.
How to calculate density
NMFTA’s density method uses the handling unit as tendered to the carrier:
- Measure the greatest length, width, and height in inches, including any overhang.
- Multiply them and divide by 1,728 to get cubic feet.
- Divide the weight in pounds by the cubic feet.
NMFTA’s own example: a pallet of boxes measuring 48 x 40 x 45 inches and weighing 450 lbs. That’s 86,400 cubic inches, or 50 cubic feet. 450 divided by 50 is 9 pcf, which falls in the 8 to under 10 range, class 100 on the scale above.
Example. Add 450 lbs to that same pallet, for 900 lbs in the same space. Density doubles to 18 pcf and the class drops to 70.
Common freight class mistakes
- Using a class from before July 19, 2025 without checking whether the item moved to density.
- Measuring the boxes and forgetting the pallet or overhang.
- Estimating weight instead of weighing the handling unit.
- Copying the class from a similar product with a different NMFC item.
- Leaving class off the bill of lading, then paying the carrier’s reclass.
When the carrier inspects and finds different dimensions or weight, it reclasses and rebills. That charge often lands after the broker already billed the customer, so the class on the quote and the class on the BOL need to match. The accessorial charges entry covers other post-delivery adjustments.