Freight Class for Box Truck Shippers: A Plain-English Guide

Freight class is one of those LTL-industry concepts that quietly leaks into box-truck pricing. Even when you’re booking dedicated capacity, the carrier still wants to know “what class is this freight” — because it shapes insurance, handling, and (sometimes) rate. Here’s the plain-English version.

What freight class actually is

Freight class is a standardized number from 50 (cheapest, densest) to 500 (most expensive, lightest and most fragile) that classifies any commodity for transit. The system is run by the National Motor Freight Traffic Association (NMFTA), and the master list is called the NMFC — National Motor Freight Classification.

The four factors that determine class

NMFC class is calculated from four factors:

1. Density — pounds per cubic foot. The denser, the lower the class (and lower the rate).
2. Stowability — does it stack? Does it require special positioning?
3. Handling — does it require special equipment, careful loading, or extra labor?
4. Liability — risk of theft, damage, or hazmat exposure.

Common freight classes you’ll see

• Class 50 — Bricks, sand, cement, palletized fluids. Heaviest, densest.
• Class 60–85 — Auto parts, many appliances, palletized canned goods.
• Class 100 — Auto accessories, paint, oil drums.
• Class 125 — Small household appliances, dishwashers.
• Class 150 — Auto sheet metal, larger appliances.
• Class 175 — Furniture (bedroom sets, dining sets).
• Class 200 — Sofas, mattresses (often).
• Class 250–300 — Bagged feathers, lampshades, plant-foam mattresses.
• Class 400 — Deer antlers (yes, really).
• Class 500 — Ping-pong balls, light furniture in rough crates. Lightest, most expensive.

When class matters for dedicated box-truck

For LTL, class is the single most important rating factor — it directly drives rate. For dedicated box-truck, you’re paying for the truck regardless of what’s in it, so class matters less for headline rate. But it still affects:

• Insurance documentation — high-class freight (electronics, antiques) may require certificate naming the shipper
• Handling expectations — class 175+ usually means “handle with care” in the carrier’s mind
• Cube vs. weight — high-class freight is usually low-density, meaning it cubes-out before it weighs-out

How to figure out your freight class

1. Calculate density: weight (lbs) ÷ volume (cubic feet)
2. Look up the commodity in the NMFC (your carrier or freight broker has access)
3. Apply density override if the actual density is higher than the listed class

Most shippers don’t calculate class themselves — they tell the carrier the commodity, and the carrier looks it up. If you’re booking with us, just describe what’s on the truck (“refrigerator,” “office furniture,” “palletized retail apparel”) and we’ll handle the rating.

Common shipper mistakes

• Underestimating cube — declared density too high, real density too low, reclass surprise on the invoice.
• Mis-declaring commodity — saying “machinery” when it’s “electronics” (very different class).
• Skipping insurance — class 250+ freight without insurance documentation is asking for trouble on a damage claim.

Bottom line

Freight class is mostly an LTL pricing tool — but it’s shorthand the entire industry uses. For dedicated box-truck shipping, you don’t need to memorize the NMFC, but you should know your commodity name and have rough density numbers ready when you quote. Get in touch and we’ll handle the class lookup for you.