NMFC Codes Explained: How to Look Up Your Classification

If freight class determines your LTL rate, NMFC codes determine your freight class. They’re the foundation of the entire LTL pricing system, and getting them right is one of the simplest ways to avoid billing surprises.

What NMFC codes are

NMFC stands for National Motor Freight Classification. It’s a standardized system maintained by the National Motor Freight Traffic Association (NMFTA) that categorizes every commodity that can be shipped via LTL.

Each product type has an NMFC number (like 116030 for canned food or 100240 for auto parts). That number maps to a freight class between 50 and 500. The class determines your per-pound shipping rate.

Think of it like a tax code for freight. Every product has a classification, and that classification determines what you pay.

How the NMFC database is structured

The database organizes commodities into 18 general commodity classes, numbered 1 through 18:

1. General freight
2. Iron and steel
3. Electrical goods
4. Machinery and tools
5. Chemical products
6. Building materials
7. Paper and printed matter
8. Agricultural products
9. Fresh fruits and vegetables
10. Automotive parts
11. Furniture
12. Textiles
13. Rubber and plastics
14. Food products
15. Glass and ceramics
16. Petroleum products
17. Miscellaneous freight
18. Hazardous materials

Within each class, specific items have their own NMFC numbers with sub-items. For example, within “Furniture” (11), you’ll find distinct entries for wooden furniture, metal furniture, upholstered furniture, and so on, each potentially at a different freight class.

Common NMFC codes and their freight classes

Here’s a reference table for frequently shipped commodities:

Note: Many NMFC codes have sub-items with different freight classes based on packaging, density, or product specifics. Always check the specific sub-item for your product.

How to determine your NMFC code

Option 1: Look it up in the database

The official NMFC database is maintained by NMFTA. Access requires a subscription ($150-$300/year), but it’s the definitive source. You can search by product description or browse by commodity class.

Option 2: Calculate by density

If you can’t find your exact product in the database, density provides a reliable guide. Calculate your shipment’s density in pounds per cubic foot:

Density = Weight (lbs) / Volume (cubic feet)

Where volume = (Length x Width x Height in inches) / 1,728

Option 3: Ask your freight provider

Freight brokers and carriers deal with classifications daily. Describe your product (material, packaging, weight, and dimensions) and they can usually tell you the correct NMFC code and class.

Sub-items matter

A single NMFC code often has multiple sub-items that change the freight class. For example, furniture might have sub-items for:

• Knocked down (KD) in cartons: Class 100
• Setup, crated: Class 125
• Setup, uncrated: Class 175

The difference between Class 100 and Class 175 is roughly 40-60% in shipping cost. Always identify the sub-item that matches how your product is actually packaged and shipped.

FAK agreements: bypassing NMFC complexity

If you ship a variety of products at different NMFC classifications, managing individual codes for every shipment is tedious and error-prone. This is where Freight All Kinds (FAK) agreements help.

Under a FAK, you and the carrier agree that all your freight ships at a single, negotiated class regardless of the actual NMFC code. This simplifies billing, reduces reclassification risk, and often saves money on your higher-class items.

FAK agreements work best when:

• You ship multiple product types regularly
• Your freight classes range across a moderate spread (e.g., Class 70-125)
• You have enough volume to negotiate

What happens when you get the code wrong

Using the wrong NMFC code leads to reclassification. The carrier inspects your shipment at the terminal, determines it should be at a different (usually higher) class, and adjusts the rate accordingly. You’ll also pay a reclassification fee of $50-$150.

Repeat reclassifications can trigger audits of your shipping history, where the carrier reviews past shipments and potentially back-bills you for class differences.

The simplest way to avoid this: weigh and measure your freight accurately, look up the correct NMFC code, and use the right sub-item for your packaging method.

How FreightSimple helps

FreightSimple helps you identify the right freight class during the quoting process. Our platform validates your shipment details and flags potential classification issues before you book, reducing the risk of expensive reclassification charges.

Get an accurate quote with the right classification.