Freight Class Explained: The NMFC Guide for LTL Shippers

What Is NMFC Freight Class?

Freight class is the standard rating system for less-than-truckload (LTL) shipments in the United States. The National Motor Freight Traffic Association (NMFTA) publishes it as the National Motor Freight Classification, or NMFC. Every commodity that moves by LTL truck gets a class under this system.

There are 18 classes, from 50 to 500. Low classes cover dense, durable goods like bricks or steel fittings. High classes cover light, bulky, or fragile goods like assembled furniture or ping pong balls. The lower the class, the lower your rate per pound.

Carriers use the class to set the base rate on every LTL shipment. The same pallet can cost twice as much at class 175 as it does at class 70. That is why getting the class right matters before you book.

Each commodity also has an NMFC item number, a specific listing in the NMFC database. The item number tells the carrier exactly which rules apply, including packaging requirements. Put it on every bill of lading. Without it, the carrier picks a class for you, and the pick is rarely cheap.

The Four Classification Factors

The NMFTA scores every commodity on four transport traits. Together they answer one question: how hard is this freight to move?

• Density. Weight per cubic foot. Dense freight uses less trailer space per pound, so it earns a lower class and a lower rate.
• Stowability. How well the freight fits with other cargo. Odd shapes, hazardous goods, and items that cannot be stacked push the class up.
• Handling. Freight that needs special equipment or extra care costs more to move. Standard boxes on standard pallets score well here.
• Liability. The risk of theft, damage, or harm to nearby freight. Fragile or high-value goods carry a higher class.

Freight Class Table: Class 50 to Class 500

Use this table as a quick reference. The density ranges follow the standard NMFC density scale as of mid-2026. Some commodities still carry exceptions for stowability, handling, or liability, so always confirm the NMFC item number before you book.

Read it like this: weigh and measure your shipment, work out pounds per cubic foot, then find the matching row. The typical commodities column shows the kind of freight that usually lands in each class.

How to Calculate Freight Density Step by Step

Density is simple math. You need a tape measure, a scale, and five minutes per pallet. Our freight calculator handles the math for you, but here is the manual method.

1. Measure length, width, and height: Measure each piece in inches at its longest points. Include the pallet, the packaging, and any overhang. Carriers always measure the full footprint, not the box label.
2. Calculate cubic feet: Multiply length by width by height in inches. Divide the result by 1,728 to convert cubic inches into cubic feet. Example: a pallet measuring 48 x 40 x 48 inches equals 92,160 cubic inches, or 53.3 cubic feet.
3. Divide weight by cubic feet: Take the total weight in pounds, including the pallet itself. Divide it by the cubic feet from the last step. A 600 lb pallet at 53.3 cubic feet has a density of 11.3 lbs per cubic foot.
4. Map the density to a class: Find your density in the table above. A result of 11.3 lbs per cubic foot falls in the 10.5 to 12 range, which is class 92.5. Repeat for every pallet in the shipment.
5. Verify the NMFC item number: Look up your commodity in the NMFC database, or ask your carrier or forwarder. The item number confirms whether the density scale applies or whether an exception changes the class.

The 2025 NMFC Changes: Density First

In 2025, the NMFTA rolled out its largest update to the NMFC in decades. The goal was simple: make density the default basis for class, and cut the maze of commodity-specific listings.

Thousands of listings moved onto a standard density scale in phased releases. As of mid-2026, most NMFC items use that scale unless the freight has clear stowability, handling, or liability issues. The standard scale uses 13 density tiers, which is why sub-classes like 77.5 and 92.5 exist.

What this means for you: accurate dimensions matter more than ever. A product that held a flat commodity rating for years may now float with its measured density. Re-check the class of every SKU you ship regularly, and do not trust a class you last confirmed before 2025.

How Freight Class Affects Your LTL Price

LTL carriers price from a base tariff. The tariff assigns a rate per 100 pounds, called CWT, for each class on each lane. Higher class means a higher rate per CWT, because light freight fills the trailer before it reaches the weight limit.

The jump between classes is steep. Moving from class 70 to class 150 can roughly double the freight charge on the same lane. Exact ratios vary by carrier and lane, but the direction never changes: class up, price up.

Here is an illustration with typical mid-2026 numbers. A 500 lb shipment on a regional lane might cost around $95 at class 55. The same shipment at class 250 could run $280 or more. Treat these as examples, since carrier discounts move real prices a lot.

Class also interacts with discounts and FAK agreements. A FAK, or freight all kinds deal, lets high-volume shippers rate several classes as one. If you ship weekly, ask your forwarder about FAK terms. And if your freight fills 12 or more linear feet, compare full truckload pricing — FTL ignores freight class entirely.

Reclassification Fees and W&I Certificates

Carriers do not take your stated class on faith. LTL terminals use forklift scales and 3D dimensioning machines to check freight as it moves through the network. Most major carriers now dimension nearly every shipment.

If the measured class differs from your bill of lading, the carrier issues a weight and inspection certificate, known as a W&I certificate. The certificate overrides your BOL. The carrier then re-bills the shipment at the correct class.

Reclass fees typically add $25 to $150 on top of the higher freight charge, as of mid-2026. Disputes are hard to win. The carrier holds photos, scale tickets, and dimensioner data, while most shippers hold none.

The fix is boring but effective. Weigh and measure every pallet before pickup, keep photos, and state real numbers on the BOL. A good ground freight partner can help you set up a repeatable measuring process at your dock.

Common Freight Class Mistakes

Most reclass bills trace back to a few repeat errors. Check your process against this list before your next pickup.

• Ignoring pallet dimensions. The pallet adds weight and height. Density math must include it. Skipping the pallet understates your cube and inflates your density.
• Guessing the class low. Some shippers pick a low class and hope it slips through. Dimensioners catch it, and the reclass fee erases any savings.
• Missing NMFC item numbers. A BOL without an item number invites the carrier to classify the freight for you. Their pick is rarely the cheaper one.
• Using pre-2025 classes. Listings that were commodity-rated may now be density-rated. Re-check every SKU against the current NMFC before you ship.
• Rounding measurements down. Carriers measure the longest point of each side, including bulges and overhang. Measure the real freight, not the carton spec sheet.

Freight Class vs International Shipping

Freight class only exists in US domestic LTL trucking. The moment your cargo crosses a border or an ocean, the NMFC no longer applies. International pricing uses different math.

Ocean freight prices by volume. LCL shipments charge per cubic meter, or CBM, under a weight-or-measure rule. Use our CBM calculator to get your chargeable volume before you request ocean quotes.

Air freight uses chargeable weight. Carriers compare the actual weight against a volumetric weight, usually at 167 kg per cubic meter, and bill whichever is higher.

Importers often face both systems on a single move. A container from Asia clears the port, then the goods travel inland as classed LTL freight. Budget your landed cost with both pricing models in mind, or the domestic leg will surprise you.

How Suaid Global Helps

Suaid Global is an asset-light freight forwarder. We do not own trucks or terminals. We book your freight through our partner network of vetted US LTL and FTL carriers, and we manage the process end to end.

For domestic moves, we help you confirm the freight class and NMFC item number before pickup. That cuts reclass surprises and keeps your invoices close to your quotes.

For import cargo, we manage the handoff from ocean or air into US trucking. One team handles the CBM math on the international leg and the class math on the domestic leg, so nothing falls between providers.

Need numbers fast? Run your dimensions through the freight calculator, or send us your commodity and specs. We will confirm the class and price the move.