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Freight class is a rating from 50 to 500 that LTL carriers use to price pallet shipments: denser freight gets a lower class and a lower rate. A pallet of bricks and a pallet of pillows can weigh the same yet cost very different amounts. One note up front: LetterAgent's shipping labels cover Canada Post Xpresspost parcels, not freight, so this is general shipping knowledge.
| Class | Density (lb per cubic foot) | Typical freight |
|---|---|---|
| 50 | 50 or more | Steel, concrete blocks, machinery |
| 55 | 35-50 | Bricks, cement, hardwood flooring |
| 60 | 30-35 | Car parts, bottled water |
| 65 | 22.5-30 | Canned goods, books |
| 70 | 15-22.5 | Food items, auto parts |
| 77.5 | 13.5-15 | Tires, bathroom fixtures |
| 85 | 12-13.5 | Crated machinery |
| 92.5 | 10.5-12 | Computers, electronics |
| 100 | 9-10.5 | Boat covers, canvas products |
| 110 | 8-9 | Cabinets, framed artwork |
| 125 | 7-8 | Small appliances |
| 150 | 6-7 | Auto sheet metal parts |
| 175 | 5-6 | Clothing, couches |
| 200 | 4-5 | Large displays |
| 250 | 3-4 | Mattresses, stuffed furniture |
| 300 | 2-3 | Wood cabinets, tables |
| 400 | 1-2 | Light fixtures |
| 500 | Less than 1 | Ping pong balls, empty crates |
LTL carriers sell trailer space, not just weight. A pallet of steel and a pallet of ping pong balls can weigh the same, but the steel occupies a small corner of the trailer while the ping pong balls fill it. The carrier prices that difference through the class: lower class, denser freight, cheaper rate. The rating scale runs from 50 (densest, lowest cost) to 500 (lightest, highest cost), and carriers quote rates per hundredweight that multiply against the class.
This is why two shipments of identical weight can get very different quotes. The class is the carrier's way of charging for the trailer space your freight actually consumes, plus how much trouble it is to handle. It is the single biggest lever on an LTL quote after distance.
Since the 2025 overhaul described below, most freight classifies straight from density. The math has two steps. First, find the volume: multiply length by width by height in inches, then divide by 1,728 (the number of cubic inches in a cubic foot), using the extreme outside dimensions including the pallet and any overhang. Second, divide the total weight in pounds by that volume. The result, in pounds per cubic foot, maps to the class in the table above.
A worked example: a pallet weighing 500 pounds and measuring 48 by 42 by 48 inches has a volume of 56 cubic feet, so its density is 8.9 pounds per cubic foot, which lands on class 110. The detail that trips people up is measuring: carriers measure the outside of the load as tendered. Forget the pallet height or the overhang, and your density number is fiction.
On July 19, 2025, the National Motor Freight Traffic Association implemented Docket 2025-1, the biggest classification overhaul in decades. Before that date, the NMFC relied heavily on commodity-specific codes: two shipments of the same density could get different classes simply because of what was inside the box. The overhaul moved far more freight onto a standardized density scale, consolidating roughly 2,000 commodity listings.
The density scale itself grew from 11 tiers to 13, adding classes 50 and 55 at the dense end for the heaviest, most compact freight, which previously had no dedicated low class. A follow-up docket continued the consolidation into 2026. The practical consequence: a freight class assigned years ago may no longer be current, and anything packed differently than before can land in a different class than the last time you shipped it.
Density is now the primary factor for most commodities, but three others can override it. Stowability covers whether the freight fits neatly with other freight in a trailer: odd shapes and items that cannot be stacked get pushed to higher classes. Handling covers special care: fragile or irregular items that need extra labor raise the class. Liability covers risk: freight prone to damage, theft, or spoilage carries a higher class to price that risk.
Items with unusual handling, stowability, or liability characteristics keep item-specific classifications rather than sitting on the density scale. So the workflow is: check whether your commodity has a special classification first, and only reach for the density table when it does not.
The carrier inspects, reclassifies, and bills you the difference plus a reclassification fee. This is one of the most expensive mistakes in LTL shipping: the corrected rate is usually much higher, and the fee sits on top of it. The most common triggers are inaccurate dimensions, missing pallet measurements, and commodity codes that went stale after the 2025 overhaul.
The defense is boring but effective: measure everything including the pallet, calculate density yourself before booking, and when your density sits near a class boundary, declare the higher class. The small difference in quoted rates is always cheaper than a reclassification.
No, and it is worth saying plainly. LetterAgent's shipping labels are Canada Post Xpresspost labels for parcels up to 5 kilograms, Canada-only. Freight class, pallets, and LTL carriers are outside what those labels cover. If your shipment needs a pallet, you need a freight broker or an LTL carrier directly, not a parcel label.
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