How To Determine Class For LTL Freight:
Understanding how to determine the freight class for LTL (Less Than Truckload) shipments is essential for accurate pricing and efficient shipping. This guide will walk you through everything you need to know about freight classification, including the NMFC code, density calculations, and more.
What is Freight Class?
Freight class is a standardized system created by the National Motor Freight Traffic Association (NMFTA). It categorizes freight into 18 classes, ranging from 50 to 500, based on four main factors: density, stowability, handling, and liability.
Lower classes (e.g., 50) = dense, durable, easy-to-ship items (lower cost).
Higher classes (e.g., 500) = lightweight, fragile, or difficult-to-handle items (higher cost).
Think of it like golf: there are 18 “holes” (classes), and your goal is to keep your score—or freight class—as low as possible to save money.
Example: Steel Bolts vs. Ping-Pong Balls
Steel bolts are dense, compact, and durable, which earns them a Class 50 rating—the lowest and cheapest.
Ping-pong balls, on the other hand, are lightweight, bulky for their weight, and fragile. They fall into Class 500, the highest and most expensive.
This contrast shows why freight class matters. Two items on the same truck can cost drastically different amounts to ship.
The National Motor Freight Classification system aka “NMFC” is a grading system for the thousands of freight commodities that move by truck in the US. There are 18 classifications (from 50-500). The classifications are based on the 4 characteristics of ship-ability (density, handling, stowability and liability). The more shippable your freight is the lower the class (50 is lowest and cheapest). It’s a lot like golf: There are 18 holes (or classifications) and you want to have the lowest score (or class) possible to avoid paying more.
4 Factors in Determining Freight Shipping Class
Freight class is a standardized classification that helps the shipping industry determine accurate freight costs. The National Motor Freight Traffic Association’s (NMFTA) system uses four main factors to classify LTL shipments. Understanding these ensures you can determine the correct freight class and avoid unexpected charges.
1. Density
Density is the most important factor because freight class is calculated based on pounds per cubic foot. A higher density usually results in a lower class number, while a lower density can increase the freight class and affect LTL shipping costs.
2. Stowability
Stowability measures how easily a shipment can be stored with other freight. Freight that is irregularly shaped, oversized, or hazardous may be assigned a higher class of your freight, since it requires more space or special conditions.
3. Handling
Handling refers to how difficult the freight is to load, move, and transport. Shipments that require special equipment or extra care are given a higher freight class, which can increase shipping costs.
4. Liability
Liability considers the risk of damage, theft, or potential harm to other shipments. High-value or fragile items are often assigned a higher class. Determining the correct freight class based on liability ensures accurate freight classification and compliance with industry standards.
Steps to Determine LTL Freight Class
1. Have a basic description of what you are shipping.
Know the different materials that make up your shipment (steel, wood, plastic, etc). This helps determine density, stowability & liability.
For example, If you are shipping steel bolts they are dense (and thus stowable) and indestructible. This gives them the highly coveted class 50 rating.
2. Determine how your shipment is packaged.
Common packaging includes pallets, skids, crates, drums, carboys, etc. See all available items here. This helps determine handling, stowability & liability.
For example, if you get the call from Pamplona to ship your next batch of bull semen, alas, you will pay dearly at class 500 (Item 059310). Bull semen is expensive, lightweight & requires special packaging with self-contained refrigerant. Not ideal for carriers.
3. Use the Freight Class Chart.
Refer to the freight class chart to find the appropriate class for your shipment based on its density. Here’s a brief overview:
Higher freight classes typically result in higher shipping costs, while lower classes can save you money.
4. Determine if your shipment is hazardous.
Information on packaging, marking and declaration of hazardous materials can be found on the FMCSA page Here.
Shipping some plutonium for the flux capacitor to Uncle Doc Brown? It's what makes time travel possible. But, it does require a lot of work on the shipper’s and carrier’s part to make sure it’s done safely. Hazardous materials must be noted on the BOL, marked & tagged on the shipment and placarded on every truck it touches along the way. Further, many haz-mats can’t go on the same truck as foodstuffs and vice-versa.
Good brokers will waive or reduce the carrier's haz-mat fee (Note: I do not condone shipping gasoline in the name of Geoarbitrage).
5. Weigh your shipment.
It’s important to have an accurate weight because it directly affects your rate. In the case of density rated items (The NMFC is continually leaning more towards this sub-system) it will also affect your class directly by altering the shipment’s density.
This needs no explanation.
6. Measure your shipment.
Use a tape measure to determine the outside dimensions of the shipment. This is hugely important especially for “density rated” items in which the density of the shipment determines the class. Carriers use the outer most dimension of the length, width and height.
For example, if you are shipping ping-pong balls they take up a lot of empty space and don’t weigh much. Good for floating in solo cups but bad for trucking. They are rated a lowly class 500.
More detailed explanation of importance of measurements: If you’re shipping a swing set with one steel pole sticking up 8 feet - 8 feet is considered the height of your shipment. Carriers make money by putting as many shipments as possible on a truck. If your shipment takes up that extra space they have to account for that unusable space (Density rated items means added revenue on your shipment and even regular shipments can be subject to the “Density minimum rule” or “excessive length” charges, which, by the way good brokers will have the latter reduced or waived)
7. Contact your freight broker.
Contact your broker or common carrier of choice to determine NMFC item number for you if you are unsure. Contacting the NMFC is a surefire way of getting the correct number but it is also a surefire way to waste lots of time and be hassled for an expensive subscription to their website (which all brokers and carriers already have)
For the purposes of getting your freight class I would recommend following the steps above once (thoroughly) to learn how the class is determined. Once you understand the process you should have most of the information you need to do everything else on the fly. Spend the extra time reading about the 6 Reasons small businesses & startups should use a freight broker.
Freight Class FAQ
-
The NMFC code is a unique identifier assigned to each freight classification, which helps streamline the LTL freight shipping process.
-
Higher freight classes often lead to increased shipping costs due to the greater liability and handling requirements associated with those items.
-
No, the freight class is determined before shipping, and changes after shipment can lead to additional charges or delays.
-
Items that are fragile, lightweight, or require special handling, such as glassware or high-value electronics, are typically assigned higher freight classes.
-
No, each freight class has a specific density range, which is crucial for determining the correct classification.
Contact TFWWI for Accurate Freight Classification
Getting your freight class right is essential for saving on LTL shipments. Contact TFWWI today to classify your freight correctly and optimize your LTL freight shipping process!