NMFC 79300 is a density-based item number in the National Motor Freight Classification, which means your freight class under it is not fixed. It’s calculated from your shipment’s pounds per cubic foot and read off a 13-step sub-item scale that runs from Class 400 at the lightest end to Class 50 at the densest.1National Motor Freight Traffic Association. National Motor Freight Classification Get the density right and the class follows automatically. Get it wrong, and a carrier reweigh will correct it for you at a price.
The 79300 Density Scale
The scale works in one direction: the denser the shipment, the lower the class, and the lower the rate. Each sub-item covers a density band in pounds per cubic foot (pcf):2National Motor Freight Traffic Association. Decoding Density: The Freight Factor You Can’t Afford to Overlook
- Sub 1 — less than 1 pcf — Class 400
- Sub 2 — 1 but less than 2 pcf — Class 300
- Sub 3 — 2 but less than 4 pcf — Class 250
- Sub 4 — 4 but less than 6 pcf — Class 175
- Sub 5 — 6 but less than 8 pcf — Class 125
- Sub 6 — 8 but less than 10 pcf — Class 100
- Sub 7 — 10 but less than 12 pcf — Class 92.5
- Sub 8 — 12 but less than 15 pcf — Class 85
- Sub 9 — 15 but less than 22.5 pcf — Class 70
- Sub 10 — 22.5 but less than 30 pcf — Class 65
- Sub 11 — 30 but less than 35 pcf — Class 60
- Sub 12 — 35 but less than 50 pcf — Class 55
- Sub 13 — 50 pcf or greater — Class 50
The practical consequence is large. A compact pallet at 35 pcf lands at Sub 12 (Class 55); a light, bulky pallet at 5 pcf lands at Sub 4 (Class 175). On the same lane, the second shipment can cost two to three times as much as the first.
For items on a density scale like 79300, the NMFTA has determined that handling, stowability, and liability don’t warrant separate adjustments beyond what the density math already captures. Density is the number that moves the class.
Calculating Density for Your Shipment
Measure the palletized load, not the product. Carriers rate what sits on their dock, including empty space inside the pallet’s footprint and any overhang. Length, width, and height go in inches. Then:
(Length × Width × Height) ÷ 1,728 = Cubic Feet
Divide the total shipment weight (product plus pallet) by cubic feet to get pcf. Match the result to the scale above.
A worked example from the NMFTA: a pallet measuring 48 × 40 × 48 inches and weighing 1,200 pounds. 48 × 40 × 48 = 92,160 cubic inches. Divided by 1,728, that’s 53.3 cubic feet. 1,200 ÷ 53.3 = 22.5 pcf, which falls in Sub 10 at Class 65.2National Motor Freight Traffic Association. Decoding Density: The Freight Factor You Can’t Afford to Overlook
The most common mistake is measuring the boxes rather than the pallet. If your product occupies a 36 × 30 area on a 48 × 40 pallet, the carrier still measures 48 × 40. That empty space lowers your effective density and pushes the shipment into a higher, more expensive class. The same thing happens when overhang isn’t included in the measurement, because the carrier will include it when they measure.
Packaging That Protects Your Density Number
Packaging doesn’t change the item number, but it changes the density the carrier records. Goods should be secured in fiberboard boxes, drums, or crates meeting the burst-strength requirements in the NMFC tariff, and those containers need to be firmly fixed to the pallet with shrink wrap or banding. Loose or sagging freight gets measured at its maximum outer dimensions, which inflates the cubic footage and drops the pcf.
Stackability also matters to cost. A pallet marked non-stackable takes vertical trailer space the carrier can’t resell to other freight, and carriers respond with higher classifications or accessorial charges, or both. If the product can take stacking weight, build the pallet so it can be stacked. If it genuinely can’t, note that clearly on the Bill of Lading rather than letting the carrier discover it in the trailer.
Recording 79300 on the Bill of Lading
The Bill of Lading is where the classification becomes contractual. In the commodity description section, record the NMFC item number (79300), the applicable sub-item number, the resulting freight class, and the shipment weight. A plain-English product description next to the code helps the driver verify the load at pickup and reduces the chance of a dispute later.
If what’s on the BOL doesn’t match what the carrier measures, the carrier reclassifies and rebills at the higher rate. The BOL is the document that holds the quoted class in place, so getting it right at the dock is far cheaper than correcting it after delivery.
When the carrier accepts the freight, they sign a copy of the BOL as a receipt. Keep that signed copy with your density calculations, dimension measurements, and weight tickets. Those records are your evidence if you need to dispute a reclassification.
If the Carrier Reweighs and Reclassifies
LTL carriers routinely pull shipments for weight and inspection checks at their terminals. If their measurements produce a different density than the BOL shows, they issue a W&I certificate, reclassify the freight, and adjust the invoice. The reweigh inspection fee alone typically runs $50 to $150, on top of the rate difference between the booked class and the new one.
Disputing the adjustment generally takes two documents: a manufacturer spec sheet showing product weight and dimensions, and a packing slip listing each item in the shipment with piece counts and weights. The totals on both need to reconcile with the BOL weight, pallet included. File quickly, ideally within a few days of receiving the adjusted invoice. The process typically takes two weeks to two months. If the dispute is approved, the carrier voids the original invoice and issues a corrected one.
The reliable way to avoid all of this is to weigh and measure every pallet before it ships. Estimates from product catalogs are where most reclassifications start. A $30 floor scale pays for itself the first time it prevents a W&I fee.
Why Density Matters More Under the 2025–2026 Dockets
The NMFC system is in the middle of a major restructuring. Docket 2025-1 took effect on July 19, 2025, consolidating roughly 2,000 commodity listings and shifting many items from commodity-based classification to density-based classification. It was the largest single set of changes in the NMFC’s history.3National Motor Freight Traffic Association. Disposition Bulletin 1371
Docket 2026-1 continues the same direction. Its amendments are scheduled to take effect on May 23, 2026, with ClassIT+ updating automatically on that date. This round consolidates items across commodity groups including clocks, ceramics, glassware, and elevator equipment, folding them into new density-based items with simpler rules.4National Motor Freight Traffic Association. Docket 2026-1
For anyone shipping under 79300, the trend reinforces what’s already true: density measurement is the skill that controls the rate. Confirm the current item description in ClassIT+ before each docket’s effective date so you aren’t shipping under a canceled or revised number, and keep your scale and tape measure close to the dock.