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Home > Guides > Maximum parcel weight
It depends on the carrier: USPS caps most parcel services at 70 lb, UPS and FedEx ground services accept up to 150 lb, and Canada Post parcels top out at 30 kg. Honest note up front: LetterAgent shipping labels are Canada-only Xpresspost capped at 5 kg, well below any of those ceilings. For anything heavier, you need the carrier's own service directly.
| Carrier and service | Maximum weight | What it is for |
|---|---|---|
| USPS (most parcel services) | 70 lb | Priority Mail, Parcel Select, and similar domestic services |
| UPS Ground / FedEx Ground | 150 lb | Heavy parcels; overweight handling fees apply well before this |
| Canada Post (parcels) | 30 kg | Expedited Parcel, Xpresspost, Priority within Canada |
| LetterAgent shipping labels | 5 kg | Canada-only Xpresspost labels via your AI assistant |
The numbers come from different histories. The 70 lb USPS limit is a legacy of postal workers handling mail by hand: it is the practical ceiling for a parcel that still moves through the postal system like mail. UPS and FedEx built ground networks around heavier freight-like parcels, so 150 lb is their standard ceiling. But "accepted" is not the same as "priced like a normal parcel." Both private carriers start charging heavy-package surcharges far below 150 lb, and anything over 70 lb at UPS also faces an over-maximum handling assessment. The ceiling is a legal limit; the surcharges are where the real money is.
Canada Post's 30 kg ceiling sits between the two systems. It covers most consumer parcels easily, but if you are shipping something like a boxed bicycle or a small appliance, you are already shopping in the freight or courier world, not the postal world.
Carriers charge by whichever is greater: actual weight or dimensional (volumetric) weight, which is the box's size converted into a weight figure. A large, light box full of pillows can bill at 30 lb while weighing 5 lb on a scale. This catches people off guard because the "maximum weight" question is really two questions: can the carrier take it, and what will the carrier charge. For bulky items, the answer to the second question is almost always "more than you expect." The fix is boring but effective: use the smallest box the item fits in safely.
This is also why carriers publish maximum dimensions alongside maximum weights. A box can be under the weight cap and still be refused or surcharged for exceeding length-plus-girth limits. Check both numbers before you pack, not after.
Use a bathroom scale for anything over a few kilograms: weigh yourself holding the packed box, then weigh yourself alone, and subtract. Postal scales at home are fine for envelopes but useless past their range. Weigh the packed box, not the item, because carriers bill on the packed weight. Then compare against the service you plan to use. If your parcel is under 5 kg and staying in Canada, a LetterAgent Xpresspost label from your AI assistant handles it: you get a quote, approve the exact price, pay once through Stripe, and receive the label PDF. Over that, or crossing a border, go to the carrier directly and compare the weight cap against the surcharge schedule.
That is freight, not parcel shipping. Freight carriers handle palletized and oversized goods, usually with scheduled pickup, and price by a completely different system (freight class, density, accessorials). The jump from parcel to freight is the point where most people should call a freight broker or the carrier's freight division rather than clicking through a parcel tool. As a rule of thumb: if it needs a pallet, it is freight.
Ready to ship it? Get a shipping label with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and get your label.
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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