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One note first: LetterAgent labels are Canada-only Xpresspost, so this US courier fee does not apply to them. An additional handling surcharge hits packages that jam up automated sorting: over 50 pounds, over 48 inches long, over 30 inches on the second-longest side, or shipped in non-box packaging like tires, tubes, or poly mailers. Any one trigger is enough.
Carriers publish four triggers, and meeting any single one adds the fee. The weight trigger is the most surprising: a package over 50 pounds of actual weight gets flagged even if it is compact, because heavy parcels have to be pulled off the belts and moved by hand. The length trigger catches anything whose longest side exceeds 48 inches. Then there is the odd one people miss: the second-longest side. A box that is 50 inches long but narrow is fine on length, yet if its width exceeds 30 inches, the fee applies anyway. Wide, flat packages are belt killers.
| Trigger | Threshold | Example |
|---|---|---|
| Actual weight | Over 50 lbs | A dense 55-lb box of books |
| Longest side | Over 48 inches | A 50-inch curtain rod box |
| Second-longest side | Over 30 inches | A wide, flat 36-inch-wide panel |
| Packaging type | Non-corrugated | Tires, tubes, poly mailers, wood crates, canvas wraps |
Some items trigger the fee regardless of size or weight, because of shape rather than dimensions. Tires and inner tubes roll, bounce, and refuse to sit flat on a conveyor. Poly mailers, the soft plastic envelopes, slide and bunch instead of riding the belt cleanly. Wood, metal, and canvas packaging have the same problem: anything that is not a rigid corrugated box gets diverted to manual handling, and the surcharge prices that detour. This catches sellers off guard because a single tire is light and small, yet it still draws the fee every time.
Usually after the fact. The surcharge is assessed during the carrier's automated audit, when the package passes through dimensioning equipment at the hub. If you entered smaller dimensions when buying the label, or did not realize a poly mailer counted as irregular packaging, the fee shows up as a post-purchase adjustment on your invoice. This is the most common "mystery charge" in small-business shipping: the label price looked right, then the adjustment arrived a week later. Measuring carefully and declaring the true packaging type at label purchase is the only reliable prevention.
Additional handling is the lower tier. It targets packages that are awkward but not enormous. The large-package surcharge sits above it, with much higher thresholds and a minimum billable weight that can multiply the cost of a big light box. A package can theoretically attract both if it is both awkward and oversized, which is why measuring twice matters. Residential and fuel surcharges are separate again, they apply to the delivery type and the market, not the package shape.
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LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
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