If you are a commercial importer — a company, trader, manufacturer or e-commerce seller clearing a container or consolidated shipment from China, not a personal parcel — then of every document in your file, the commercial invoice has the biggest impact on what you pay at the border. It is the supplier's bill of sale, but to customs it is first and foremost the basis of customs value: your duty and import VAT/GST are calculated from the figure on this one document. Get a single field wrong and instead of a fast release you get a document request, a customs-value adjustment, or — at worst — a suspicion of under-declaration. Below is what the document is, which fields are mandatory, and how to check it before shipment.
This article is part of our series on import documents from China. Here we take one document and break it down in detail.
What a commercial invoice is, and its three roles
A commercial invoice is the final bill of sale issued by the seller (the factory) to the buyer (you). Unlike the other papers in your file, it performs three roles at once:
- Commercial. It is a legally binding bill: it confirms the sale, the amount, the currency and the payment terms agreed between the parties.
- Customs. It is the primary document from which customs determines the customs value — the base for duty and import tax. Under the WTO methodology (the Customs Valuation Agreement), the primary method is transaction value, defined as the "price actually paid or payable" for the goods. That price is exactly what customs reads off the invoice.
- Accounting. It is a source document for currency control at your bank, for your books, and for reconciliation against the contract.
Because of that customs role, the invoice is not a formality. Customs does not take the number on trust — it reconciles the invoice against the contract, the payment, the bill of lading and the packing list. Mismatches between those documents are the number-one cause of delays.
Mandatory fields on a commercial invoice
There is no single mandated template, but there is a set of details without which the invoice will not be accepted for clearance. Check that each is present:
- Full seller and buyer details — legal names, addresses and contact information for both parties.
- Invoice number and date — a unique number that must match the references used in your other documents.
- Full description of the goods — specific, with no vague wording like "goods" or "samples". Material, model, purpose, specifications.
- HS code — the tariff classification that sets the duty rate. How to find it is covered in how to determine an HS code.
- Quantity and units — pieces, sets, weight, linear metres and so on.
- Unit price and total — broken down per line with a grand total.
- Currency — usually USD, and it must match the currency of the contract and the payment.
- Incoterms and named place — for example FOB Ningbo or CIF Rotterdam. See Incoterms 2020 for China imports.
- Country of origin — affects the duty rate and any preferential tariff.
- Payment terms — deposit, balance, credit terms and banking details.
- Net and gross weight — must match the packing list.
- Seller's signature and stamp — an uncertified invoice raises questions.
Proforma invoice vs commercial invoice
These two documents are frequently confused, and that is exactly where newcomers slip up. A proforma invoice is a preliminary quotation-invoice the factory issues before payment: you use it to agree the price, pay the deposit and open the contract. It is essentially an offer in invoice format — it is not the final sales document.
A commercial invoice is issued after the goods are produced and ready to ship, and it reflects the actual transaction. This is the one that goes to customs clearance.
A proforma is for agreeing and paying. A commercial invoice is for clearing. You cannot submit a proforma in place of a commercial invoice for final release.
How customs uses the invoice for valuation
The primary method for determining customs value is the transaction-value method: the base is the price actually paid or payable for the goods (the invoice total), plus statutory additions — for example the cost of freight and insurance to the border where they are not already included in the price under your Incoterms. This is why the delivery terms on the invoice are critical: on FOB, customs adds freight and insurance to the customs value; on CIF, they are already inside the price.
From there the logic is straightforward: customs applies the duty rate for your HS code to the customs value, then applies import VAT/GST on the customs value plus duty. In other words, the invoice sets off the entire chain of payments. For how this plays out across the whole clearance, see our guide to China customs clearance for business.
Common errors and the under-invoicing trap
The most frequent causes of delays and adjustments:
- A vague goods description — "parts", "goods", "gifts". Customs cannot classify the item and holds the release.
- A value that mismatches the contract and the payment — the invoice total does not agree with the contract or the funds transferred. That is a red flag.
- Missing Incoterms or named place — it is unclear what the price includes, so customs cannot value the goods correctly.
- Weight that does not match the packing list and bill of lading — a discrepancy between documents invites inspection.
- A wrong or missing HS code — leads to the wrong duty rate.
Then there is under-invoicing. The temptation to "ask the factory to write a lower figure so you pay less duty" ends badly. Declaring an understated value on the invoice while the real payment is higher — so-called double invoicing — is customs fraud, illegal in every WTO member country. Customs compares your value against risk profiles and market prices: if the figure reads "below market", it triggers a customs-value uplift, back-assessed duty and tax, penalties, and in serious cases criminal prosecution. Savings on paper turn into far larger losses.
How to check the invoice before shipment
The invoice should be checked before the container leaves, not at the border. A practical checklist:
- Reconcile the amount, currency and party details against the contract and the payment orders — everything should match to the figure.
- Confirm the goods description is specific and matches the actual cargo and the HS code.
- Verify that Incoterms and the named place are stated and reflect what you actually paid for.
- Cross-check net/gross weight and package count against the packing list.
- Confirm the invoice number and date are consistent with the rest of the document set.
- Check the factory's signature and stamp are present.
At Silk Way Sourcing we work on a full-cycle basis — from factory search through delivery and clearance — so we check the invoice as part of one coherent file: reconciling it against the contract, the inspection and the transport documents while the goods are still in China. Over 7 years and 3,500+ deliveries with 340+ verified suppliers, we have seen every kind of flawed invoice and know exactly what stops a shipment at the border. Preparing clearance documents is handled by our documentation support service, and the clearance itself by our customs broker in Ukraine.
We'll check your invoice before shipment
Don't wait for the container to sit at customs. Send us your invoice and contract — we'll reconcile the fields, sanity-check the customs value, and flag the risks before shipment.
- Email: contact@silkwaysourcing.com
- WhatsApp: +380 97 883 4765
*This article is informational. Customs rules and rates as of 2026 should be verified against current law and with your broker at the time of shipment.*
