Introduction
Understanding NMFC codes and freight class is key for accurate classification and cost reduction on shipments. This blog explains what these concepts are to provide you with practical tips and tools to streamline your shipping processes and save money.
Understanding NMFC Codes
NMFC codes, or National Motor Freight Classification codes, are standardized codes developed by the National Motor Freight Traffic Association (NMFTA) to classify commodities for shipping. These codes ensure that goods are classified uniformly, which helps in determining shipping costs and handling requirements.
Key Factors Determining NMFC Codes
NMFC codes are determined based on four key factors:
- Density: This measures how much space a shipment occupies relative to its weight. See our guide to LTL weight and size limits for carrier-specific thresholds. High-density items are generally more favorable for shipping.
Example: A pallet of bricks is denser than a pallet of ping-pong balls, making it cheaper to ship.
- Handling: This factor considers the ease or difficulty of handling the shipment. Items that are easy to handle are assigned a lower NMFC code.
Example: A box of nuts and bolts is easier to handle compared to a large, fragile chandelier.
Stowability: This assesses how easily items can be stored in a carrier’s vehicle. Uniformly shaped items that stack easily are more favorable. Meeting LTL packaging requirements keeps your class assignment accurate.
Example: Stacked boxes versus a rolled-up carpet.
Liability: This includes the risk of damage, theft, or other liabilities. High-risk items have higher NMFC codes.
Example: Hazardous materials versus non-hazardous materials.
How to Determine Your NMFC Code
To determine your NMFC code:
- Measure the dimensions and weight of your item accurately — national LTL carriers inspect 75 to 95 percent of shipments using automated dimensionalizers at their terminals, so estimating dimensions is not a risk worth taking.
- Calculate the density (weight divided by cubic feet).
- Use an NMFC code lookup tool like ClassIT® to find the corresponding code.
- Cross-reference with similar items to ensure accuracy.
What is Freight Class?
Freight class is a standardized classification system used to determine shipping costs based on NMFC codes. It ranges from Class 50 to Class 500, with lower classes being cheaper to ship.
Criteria for Determining Freight Class
Freight class is determined using the same four factors as NMFC codes:
- Density: Lower density generally means a higher freight class.
- Handling: More difficult handling results in a higher class.
- Stowability: Poor stowability leads to a higher class.
- Liability: Higher risk items are placed in higher classes.
How to Calculate Your Freight Class
To calculate your freight class:
- Measure and weigh your shipment.
- Use a density calculator to determine its density.
- Refer to a freight class chart to find the class that matches your shipment’s density.
Benefits of Accurate Classification
Accurate NMFC and freight class classification offers several benefits:
- Cost Savings: Avoid overpaying for shipping by ensuring your items are correctly classified.
- Efficiency: Streamline your shipping process and reduce delays.
- Avoidance of Reclassification Issues: Prevent additional charges and delays from misclassification.
Common Mistakes and How to Avoid Them
- Incorrect Measurements: Always measure dimensions and weight accurately.
- Not Using Updated Codes: NMFC codes are updated regularly; always use the latest version.
- Ignoring Special Handling Requirements: Factor in any special handling needs to avoid surprises.
Practical Tools and Resources
Use these tools and resources to help with your classification:
- NMFC Code Lookup Tool: Access the ClassIT® tool for accurate NMFC codes.
- Density Calculators: Available online to help you calculate freight density.
- Freight Class Charts: Use this chart to determine your freight class based on density.
Preparing for NMFC Reclassification
The NMFC system is reviewed and updated on a rolling basis by the National Motor Freight Traffic Association, and periodic reclassifications can move your commodities into a different freight class. When that happens, the rate you were quoting yesterday may not be the rate you pay tomorrow. The single biggest shift in recent memory, the NMFTA’s Classification Reimagined initiative, moved many commodities toward a density-based model, which rewards shippers who know and document the density of what they ship. Categories most affected include plastics, textiles, automotive parts, and packaging supplies, where a small change in packaging can move the class.
You do not need to track every bulletin to stay protected. You need a repeatable process.
How to prepare before a reclassification takes effect
- Audit your most-shipped items first. Pull your top 20 commodities by volume and confirm the class on file for each one.
- Measure real density. Calculate pounds per cubic foot for each item using actual packaged dimensions and weight, not estimates. Density is what most reclassifications hinge on.
- Update your item master and BOLs. Stale class codes on your bills of lading are the most common cause of reclassification fees and surprise rebills.
- Flag your reinspection risk. Items near a class breakpoint are the ones carriers are most likely to reweigh and reclassify in their terminals.
- Document everything. Keep scale tickets, photos, and dimension records so you can dispute a reclass instead of just paying it.
- Talk to your provider early. A quick review before the change date is far cheaper than a rebill after it.
The cost of getting this wrong adds up fast. A shipment quoted at class 175 that gets reinspected and bumped to class 250 can cost a few hundred dollars more per load, and that difference multiplies across peak-season volume.
If you are not sure where your commodities land, request a quote and freight class review and we will confirm your classes before the next bulletin does it for you.
Conclusion
Understanding and accurately applying NMFC codes and freight class is essential for efficient and cost-effective shipping. By following this guide, you can streamline your shipping processes, reduce costs, and avoid common pitfalls. For a full overview of how LTL shipping works, see our LTL shipping guide. For more information and support, feel free to contact us.