You get a clean LTL quote — say $500 — book the shipment, and then the invoice lands at $3,500. Nothing changed about your freight. So what happened?
Welcome to accessorial charges: the rules carriers use to re-rate freight that doesn’t behave like a neat, dense, palletized box. If you ship steel, machinery, generators, lumber, or anything heavy and odd-shaped, these rules are aimed squarely at you. Here’s how each one works — and why partial flatbed sidesteps the whole game.
1. Density Minimum Charge
LTL carriers price partly on density — weight per cubic foot. Light-but-bulky freight has low density, so a density minimum kicks in and bills your shipment as if it were far heavier than the scale says. A 600-lb crate that eats a lot of space can be rated like it weighs 2,000+ lbs.
2. Cubic Capacity Charge
When a shipment crosses a cubic-foot threshold at low density (commonly around 750 cubic feet), the carrier re-rates the entire load upward. One oversized item can trip the rule and rewrite the price of everything on the bill.
3. Linear Foot Charge
Long freight eats trailer length other freight can’t share. Once your shipment occupies a certain number of linear feet (often 12+), the carrier bills per linear foot — frequently as if those feet were packed with dense, heavy freight. Structural steel, pipe, and long machinery trigger this constantly.
4. Capacity Load Charge
When a shipment ties up a large share of trailer capacity, carriers add a premium for the space and weight you’re monopolizing. Stack it on top of the charges above and the original quote becomes a rounding error.
How $500 becomes $3,500
| Line item | Amount |
|---|---|
| Base LTL quote | $500 |
| Density Minimum Charge | +$650 |
| Cubic Capacity Charge | +$900 |
| Linear Foot Charge | +$750 |
| Capacity Load Charge | +$700 |
| Total | $3,500 |
None of these are scams — they’re how the LTL network protects itself from freight it isn’t built for. The problem is that your freight is exactly that kind of freight.
The partial-flatbed alternative
Partial flatbed (Flatbed LTL) prices differently: you’re quoted for the deck space your freight actually occupies, on a trailer built for heavy, open-deck loads. There’s no density re-rating, no cubic threshold, no linear-foot multiplier — one clear number, up front.
- Heavy, tall, long, odd-shaped freight is the norm, not the exception
- You pay for your footprint, not the whole trailer
- No surprise re-rating after the load is already moving
If your freight keeps tripping LTL accessorials, that’s a signal it belongs on a flatbed — just not necessarily a whole one.
Shipping something heavy or awkward? Get an honest partial-flatbed quote or call (800) 831-5376.