NMFC Freight Classification Guide: Understanding Freight Classes for Better Rates

NMFC Freight Classification Guide: Understanding Freight Classes for Better Rates

The National Motor Freight Classification (NMFC) system plays a critical role in determining shipping costs for less-than-truckload (LTL) freight. Understanding how this system works can help shippers optimize their packaging, reduce costs, and avoid unexpected reclassification charges. This comprehensive guide explains everything you need to know about freight classes and how they impact your bottom line.

What is the National Motor Freight Classification (NMFC)?

The National Motor Freight Classification (NMFC) is a standardized freight pricing system established by the National Motor Freight Traffic Association (NMFTA). It serves as the industry standard for categorizing shipments based on transportability characteristics rather than product type alone.

Key Information:

The NMFC system assigns every commodity a specific freight class from 50 to 500, with each class representing a different shipping cost level. Lower class numbers generally indicate lower shipping costs.

Unlike simple weight-based pricing, the NMFC system considers multiple factors that affect transportation costs and carrier liability. This standardization helps ensure consistency across the freight industry and provides a framework for carriers to establish rates.

The Four Primary Factors That Determine Freight Class

The NMFC system evaluates four key characteristics to determine which of the 18 freight classes (50-500) a shipment belongs to:

Density

The weight of the shipment relative to its volume (pounds per cubic foot). Higher density items typically receive lower freight classes and lower rates.

Stowability

How easily freight can be stored and transported alongside other items. Items that are oddly shaped, hazardous, or require special handling may receive higher classes.

Handling

The ease or difficulty of loading, transporting, and delivering the freight. Items requiring special equipment or extra care are assigned higher classes.

Liability

The probability of theft, damage, or causing damage to other freight. This includes value, perishability, and fragility. Higher liability items receive higher classes.

Important Note:

While all four factors are considered, density is often the most influential factor in determining freight class for most shipments. This is why density calculators are such valuable tools for freight shippers.

Understanding the 18 NMFC Freight Classes

The NMFC system consists of 18 different freight classes, ranging from Class 50 to Class 500. Each class represents a different density range and shipping cost level:

Freight Class Density Range (PCF) Typical Commodities Cost Level
Class 50 50+ PCF Steel, brick, cement, machinery parts Lowest
Class 55 35-50 PCF Bricks, hardwood flooring, construction materials Very Low
Class 60 30-35 PCF Car accessories, tools, canned goods Low
Class 65 22.5-30 PCF Car parts, bottled beverages, books Low
Class 70 15-22.5 PCF Auto engines, food items, cast iron Low-Medium
Class 77.5 13.5-15 PCF Tires, bathroom fixtures Medium
Class 85 12-13.5 PCF Crated machinery, cast iron stoves Medium
Class 92.5 10.5-12 PCF Computers, monitors, refrigerators Medium-High
Class 100 9-10.5 PCF Car covers, boat covers, canvas Medium-High
Class 110 8-9 PCF Cabinets, framed art, table saws High
Class 125 7-8 PCF Small household appliances, vending machines High
Class 150 6-7 PCF Auto sheet metal parts, bookcases Very High
Class 175 5-6 PCF Clothing, couches, stuffed furniture Very High
Class 200 4-5 PCF Sheet metal parts, aluminum table, mattress sets Very High
Class 250 3-4 PCF Bamboo furniture, mattresses, plasma TVs Extremely High
Class 300 2-3 PCF Wood cabinets, tables, chairs, model boats Extremely High
Class 400 1-2 PCF Deer antlers, light fixtures Premium
Class 500 Less than 1 PCF Ping pong balls, insulation, foam Highest

How NMFC Freight Classification Affects Shipping Costs

The freight class assigned to your shipment directly impacts your shipping costs in several ways:

Direct Cost Impact

  • Base Rate Determination: Higher freight classes (e.g., Class 500) have significantly higher base rates than lower classes (e.g., Class 50).
  • Pricing Multiplier: Each class has a different pricing multiplier that carriers apply to their base rates.
  • Volume Discounts: Higher volume shippers may negotiate better rates for specific freight classes they ship regularly.

Reclassification Fees

If a carrier determines that your freight was incorrectly classified:

  • They can reclassify the shipment to a higher class
  • Apply reclassification fees (often $25-$50 per occurrence)
  • Charge the difference between the original and correct class rates
  • Create delays in delivery as the shipment is held for reclassification

Warning:

Reclassification fees and adjustments can add significant unexpected costs to your shipping budget. In some cases, these adjustments can double or triple the original quoted rate.

Using NMFC Codes for Accurate Classification

In addition to freight classes, the NMFC system uses specific numeric codes to identify different commodities with greater precision:

NMFC Code Structure

Each NMFC code typically consists of:

  • A 6-digit number that identifies the specific commodity
  • A sub-number that provides more detailed classification
  • For example: NMFC item 156600, sub 2

Finding Your NMFC Code

To find the correct NMFC code for your shipment:

  1. Consult the National Motor Freight Classification directory (requires subscription)
  2. Contact your freight carrier or broker
  3. Use online NMFC code lookup tools
  4. Work with a logistics professional

Strategies to Optimize Your Freight Class and Reduce Costs

Understanding how freight class impacts your shipping costs allows you to implement strategies to achieve better rates:

Optimize Packaging

  • Use smaller, more compact packaging to increase density
  • Eliminate empty space with proper packing materials
  • Consider alternative packaging materials that weigh less
  • Consolidate multiple small items into a single denser package

Palletize Efficiently

  • Stack items properly to maximize density
  • Use standard pallet sizes (typically 48" x 40")
  • Consider plastic pallets which weigh less than wood
  • Ensure pallets are properly wrapped and secured

Use Density Calculators

  • Calculate your freight density before shipping
  • Determine the most cost-effective packaging approach
  • Document your density calculations for carriers
  • Provide accurate dimensions and weight information
🚛 Try Our Free XPO Density Calculator

Provide Accurate Documentation

  • Include correct NMFC codes on all shipping documents
  • Accurately describe commodity contents
  • Include density calculations when applicable
  • Keep photographic evidence of properly packaged freight

Pro Tip:

For businesses that ship regularly, consider negotiating with carriers for FAK (Freight All Kinds) rates that allow multiple products to be shipped at a single freight class regardless of their individual classifications.

Common Freight Classification Mistakes to Avoid

Even experienced shippers can make mistakes with freight classification. Here are some common pitfalls to avoid:

Critical Errors That Lead to Reclassification

  • Misrepresenting dimensions: Failing to measure the shipment accurately or not including packaging dimensions
  • Inaccurate weight: Not accounting for pallet weight or providing estimated rather than actual weights
  • Using outdated NMFC codes: The NMFC system is updated regularly, and old codes may no longer be valid
  • Incomplete descriptions: Not providing enough detail about the commodity being shipped
  • Ignoring density calculations: Assuming a product's class based on previous shipments rather than calculating current density
  • Failing to account for mixed shipments: Not properly documenting when multiple items with different classes are shipped together

FAQs About NMFC Freight Classification

How often are NMFC classifications updated?

The National Motor Freight Traffic Association (NMFTA) typically updates the NMFC classification system multiple times per year. Major changes are usually published quarterly, with continuous smaller updates. It's important to stay current with these updates as they can affect your shipping costs.

Can I challenge a freight reclassification?

Yes, you can dispute a reclassification if you believe it was made in error. To successfully challenge a reclassification:

  • Provide documentation of the actual dimensions and weight
  • Submit photographic evidence of the properly packaged freight
  • Reference the correct NMFC code for your commodity
  • Include density calculations that support your claimed class

What is FAK (Freight All Kinds) pricing?

FAK (Freight All Kinds) is a negotiated agreement between a shipper and carrier that allows multiple items with different freight classes to be shipped under a single, blended class rate. This simplifies billing and can provide cost advantages for shippers who regularly transport mixed freight. FAK rates are typically negotiated based on shipping volume and the average classification of goods shipped.

Does NMFC classification apply to international shipments?

The NMFC system is primarily used for domestic LTL shipping within the United States. International shipments generally use different classification systems, such as the Harmonized System (HS) codes. However, for shipments originating in the US before going international, NMFC codes may still be applied for the domestic portion of the journey.

Conclusion: Mastering Freight Classification for Better Shipping Costs

Understanding the NMFC freight classification system is essential for any business that ships goods using LTL carriers. By mastering the principles behind freight classes, calculating density correctly, and optimizing your packaging strategies, you can:

  • Achieve lower freight classes and reduced shipping costs
  • Avoid costly reclassification fees and adjustments
  • Improve shipping efficiency and transit times
  • Make more accurate shipping cost projections
  • Negotiate better rates with carriers based on accurate classification

The time invested in understanding and properly applying NMFC classification principles will pay significant dividends through reduced shipping costs and fewer logistical headaches. Start by using density calculators to determine your freight's class, then implement the optimization strategies outlined in this guide to maximize your shipping efficiency.

Next Steps for Freight Optimization

To take your freight shipping efficiency to the next level:

  1. Calculate the density of your commonly shipped items (use our free calculator)
  2. Document the NMFC codes for your regular commodities
  3. Review packaging methods to optimize for density
  4. Train shipping staff on proper measurement and classification
  5. Consider consulting with a logistics professional to identify additional savings opportunities