Almost all U.S. LTL carriers use NMFC freight classes, although some are attempting to move to a dimensionally-based system.

CWT stands for hundredweight. LTL shipments are priced “per 100 pounds,” “cwt,” or “per hundredweight.” This means that a 400 lb shipment priced at $25 CWT would cost $100, not including accessories or specialty services.

Some items, such as car transmissions, have a specific class no matter how heavy or big they are. This is called a fixed class. Items can be assigned a fixed class if the value and transportability very rarely change.