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Export Documents

Every commercial shipment leaving the UK needs a commercial invoice. It's the document that customs authorities at the destination use to assess whether import duty and taxes are owed — and how much. Get it wrong and your shipment can be delayed, charged incorrectly, or returned. Get it right and it clears customs without friction. Here's exactly what to include.

What a Commercial Invoice Actually Is

A commercial invoice is a formal record of a transaction between a UK exporter and an overseas buyer. It serves two purposes simultaneously: it's a payment request from seller to buyer, and it's the primary customs document that determines the duty and tax liability on your goods at the destination border.

Unlike domestic invoices, the commercial invoice for an export must contain specific fields that customs authorities require. Missing information doesn't just cause administrative inconvenience — it can hold a shipment at the border until a revised document is provided, at the importer's expense. See the full list of documents required for UK exports for context on where the commercial invoice fits in.

The Ten Fields That Must Be on Every Commercial Invoice

1. Exporter details: your full business name, address, country, EORI number, and VAT number if applicable.
2. Consignee details: the buyer's full name, address, and country. If the recipient differs from the buyer (e.g. a gift), include both.
3. Invoice number and date: a unique reference number and the date the invoice was issued.
4. Description of goods: a specific, accurate description of what is being shipped. "Goods" or "merchandise" is not acceptable. Write "12 handmade ceramic mugs, glazed stoneware" not "ceramics."
5. HS/commodity code: the 6-digit harmonised system code (or 10-digit UK code for import declarations). Customs uses this to determine the duty rate.
6. Quantity and unit of measure: the number of items, stated in units, kilograms, metres, or whatever unit applies to your goods.
7. Unit price and total value: the price per unit and the total invoice value. The currency must be stated explicitly.
8. Currency: GBP, EUR, USD, or whichever currency the transaction is denominated in. Customs will convert to assess duty.
9. Country of origin: where the goods were manufactured or substantially produced. This determines whether preferential duty rates apply under any trade agreement.
10. Incoterms: the agreed delivery terms (e.g. DAP, DDP, EXW). These determine who is responsible for customs clearance and who bears the risk during transit.

Common Mistakes That Cause Delays

Vague descriptions. Writing "gifts," "samples," or "clothing" on a commercial invoice is one of the most common errors UK exporters make. Customs requires enough detail to classify the goods and assess their value. "Ladies' woven cotton dress, size 12" is an acceptable description. "Ladies' clothing" is not.

Undervaluing goods. Deliberately understating the value to reduce the buyer's import tax liability is customs fraud, not a clever workaround. If discovered, the shipment will be held, the correct duty assessed, and penalties may follow. For gifts, the commercial invoice must still reflect the true market value.

Missing the HS code. Many UK exporters omit the commodity code, particularly on smaller shipments. This forces the customs authority to assign one themselves — and they may assign the one that attracts the highest rate for the product category.

Wrong currency. Stating the value without a currency, or stating it in the wrong currency, forces a manual review. Always include the three-letter ISO currency code (GBP, EUR, USD).

These are also among the most common export mistakes UK businesses make — easily avoided with a properly structured document.

Commercial Invoice vs Proforma Invoice

A proforma invoice is a draft or estimate issued before a transaction is finalised — typically used to get import approval or a letter of credit from the buyer's bank. It looks like a commercial invoice but explicitly states "Proforma Invoice" and does not trigger a payment obligation.

A commercial invoice is issued after the goods are dispatched and represents the final, binding record of the transaction. Customs want the commercial invoice, not a proforma. Using a proforma where a commercial invoice is required is a frequent source of customs delays.

How Many Copies Do You Need?

For most international shipments, you'll need the commercial invoice attached to the outside of the parcel (in a pouch or envelope marked "documents") plus two or three copies for the customs agent or freight forwarder. Many courier services now accept electronic copies as part of their online booking system — check with your carrier.

For high-value or regulated goods, the destination country may require additional copies. EU member states typically need three copies; some Middle Eastern and African countries require five or more, sometimes stamped by a Chamber of Commerce.

Let the Software Do It

Filling in a commercial invoice correctly by hand or in a spreadsheet introduces risk at every field. ClearDocs generates correctly formatted commercial invoices automatically — you enter your exporter and consignee details once, add your line items with HS codes and values, and the document is produced to the correct international standard. The same data entry simultaneously generates your packing list and, for EU shipments, your statement of origin.