NMFC Code (National Motor Freight Classification)

An NMFC code is a unique identifier assigned to a specific commodity that determines how it's classified and priced in LTL shipping. Published by the National Motor Freight Traffic Association (NMFTA), the NMFC system catalogs thousands of products – from electronics to food ingredients to industrial chemicals – and assigns each a code that maps to a freight class between 50 and 500. The code accounts for the commodity's density, handling requirements, stowability, and liability characteristics.

Each NMFC code can have multiple sub-codes that further refine the classification based on packaging, density ranges, or specific product variations. For example, canned food and frozen food may fall under different NMFC codes – or different sub-codes – even though they're both "food." The sub-code distinction matters because it can shift the freight class and therefore the rate. Shippers need to match their products to the correct NMFC code and sub-code, not just the general category, to ensure accurate pricing and avoid reclassification.

NMFC codes appear on every LTL bill of lading and are the basis for carrier pricing. If the code on the BOL doesn't match the actual commodity – or if the declared density doesn't align with what the carrier measures – the shipment gets reclassified and the invoice adjusted, usually upward. Reclassification disputes are one of the most common sources of friction between shippers and LTL carriers, and they're almost entirely preventable with accurate product data at the point of shipment creation.

The NMFTA periodically updates NMFC codes, adding new classifications and adjusting existing ones. Shippers who maintain an up-to-date item master with accurate dimensions, weights, and NMFC assignments avoid the majority of reclassification issues and the billing surprises that come with them.