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A commercial invoice is the document customs uses to decide what your shipment is and what duty it owes. The shipper creates it, listing both parties, a description of the goods, HS tariff codes, country of origin, and the value. It is not a bill: it is a declaration. Note up front: LetterAgent labels are Canada-only Xpresspost, so you will not file one through us.
| Field | What goes in it | Why customs cares |
|---|---|---|
| Seller and buyer details | Names, addresses, contact info | Establishes who is exporting and importing |
| Description of goods | Plain-language description, quantities | Identifies what is actually in the box |
| HS tariff code | 6-10 digit classification per item | Sets the duty rate |
| Country of origin | Where the goods were made | Determines trade-agreement eligibility |
| Value and currency | Transaction value per item and total | The base the duty is calculated on |
| Incoterms | DDP, DDU, and similar | Says who pays the duties |
The shipper does, not the carrier. If you are sending goods across a border, the commercial invoice is your declaration, and you are responsible for its accuracy. In practice, most carrier platforms and marketplaces generate the form for you from the customs details you enter at label purchase, which is why many sellers never see a blank one. But the data is still yours: the HS code you pick and the value you declare are what the customs officer works from. The carrier just transmits it.
More than anything else on the form. The Harmonized System code classifies your product in the international tariff schedule, and the duty rate attaches to the code, not to your description. Two similar products can carry very different rates under different codes, which is why vague descriptions like "gift items" or "parts" cause trouble: the officer cannot verify the classification and may reclassify the goods themselves, usually not in your favor. Specific beats clever every time. "Cotton men's t-shirts" clears faster and fairer than "apparel."
A proforma invoice is a quote dressed as an invoice. It is issued before the sale, often so the buyer can arrange payment or an import license, and it carries no customs weight because no goods have moved yet. The commercial invoice is issued for the actual shipment and is the document customs clears against. The confusion arises because they look alike. The rule is simple: if goods are crossing the border with it, it needs to be the commercial version, with final values and the real transaction details.
Undervaluation is the classic one. Declaring a token value to dodge duty is misdeclaration, and customs officers see it daily; the penalty is reassessment at their value plus fines, and repeat offenders get their shipments opened as a matter of routine. Missing country of origin is another quiet killer, because origin determines whether a trade agreement wipes the duty to zero. And mismatched paperwork, where the invoice says one thing and the box contains another, is how a two-day clearance becomes a two-week inspection. The invoice is a legal declaration, so treat every line like it will be read by someone with the authority to open your box.
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