Errors on the commercial invoice – 7 major mistakes that will hold your goods [2026]

In international transport, the commercial invoice is not only an accounting document – it is the most important customs document. The customs agency generates the declaration based on it, and the officer calculates duty and VAT.

In practice, at easyclearance.pl we observe that 90% of delays in clearance result from invoice errorsA "standard" VAT invoice issued by accounting software often does not meet HMRC customs requirements.

Here are the 7 most common mistakes that can cost you vehicle delays, financial penalties, or loss of customs preferences.

1. Missing or incorrect Incoterms® conditions

This is an absolute classic. The invoice includes the price but does not state, who pays for transport and duty.

• Error: No rule Incoterms or entering just the name (e.g. "Incoterms 2020") without a specific rule (e.g. DAP).
• Effect: The customs agency does not know whether to include transport costs in the customs value (duty base) and who the importer is. Clearance is on hold pending clarification.
• Solution: Always enter: `Rule + Place`, e.g. `DAP London, UK (Incoterms 2020)`.

2. Unclear description of goods ("Parts", "Accessories")

Customs systems require precision.

• Error: Description types: "Spare parts", "Gift", "Samples", "Miscellaneous".
• Effect: The Customs Office may request a goods inspection because the description does not allow HS code verification.
• Solution: Precision. Instead of "Parts", write: "Steel bolts for car engines". Instead of "Clothing", write: "100% cotton women's trousers". The description must allow identification of the goods.

3. Undervalued goods ("Proforma" at 1 EUR)

Common mistake when shipping samples or freebies.

• Error: Issuing invoices for "1 EUR" or "0 EUR" despite the goods having a real market value.
• Effect: Suspicion of undervaluation. UK Customs may challenge the value and estimate it independently (usually to the importer’s disadvantage) + impose a penalty.
• Solution: Even samples must have a declared market value for customs purposes (Value for Customs Purposes Only). You may add the note: `Free of charge. Value for customs purposes only.`

4. Missing or incorrect HS (CN) codes

• Error: Invoice without customs tariff codes or codes shortened to 4 digits.
• Effect: The customs agent must "guess" codes based on the description. If guessed incorrectly, the importer will pay incorrect duty (too high or too low – risking adjustment and penalty).
• Solution: Provide full, 8-digit HS codes for each invoice item.

5. No Certificate of Origin (TCA Preferences)

This is a mistake that costs real money.

• Error: The goods are produced in the EU, but the invoice does not contain the legally required statement on preferential origin.
• Effect: The importer in the UK must pay full customs duty rate (e.g. 12% on clothing, 10% on cars), even though it could be 0%.
• Solution: If the goods are from the EU, add the following phrase on the invoice:

"The exporter of the products covered by this document (Exporter Reference No ... ) declares that, except where otherwise clearly indicated, these products are of ... preferential origin."

6. Lack of EORI numbers

• Error: The invoice contains only the VAT ID, with no EORI numbers for the sender or recipient.
• Effect: Unable to submit declaration in the system. EORI is mandatory.
• Solution: Clearly state in the invoice header:

`Exporter EORI: PL...` `Importer EORI: GB...`

7. Weight discrepancy (Net weight > Gross weight)

Sounds like a school error, but it often occurs in ERP systems.

• Error: The net weight on the invoice is greater than the gross weight, or the sum of item weights does not match the weight on the consignment note (CMR).
• Effect: The customs system will automatically reject the declaration (validation error).
• Solution: Check weights before shipment. Remember: Gross Weight = Goods Weight + Packaging (pallet, carton). It can never be less than net weight.

Pre-shipment checklist summary

Before sending the invoice to the customs agency, check these 7 points:

• Is there an EORI number for the sender and recipient?
• Are Incoterms terms stated with a named place?
• Is the goods description unambiguous?
• Are HS codes provided (minimum 6-8 digits)?
• Does gross/net weight make sense?
• Is the value market-based (even for freebies)?
• Is there an origin statement (if you want 0% duty)?

Eliminating these errors will speed up your clearance by 90%.

What the current official guidance means in practice

For operational work, the current procedural rules, declaration fields and relief conditions should be checked directly against the official guidance. For this topic, the core reference points are European Commission, GOV.UK / HMRC.

Official sources

• EU Commission (Customs procedures) — European Commission, 2026-03-04
• UK GOV (Importing into the UK) — GOV.UK / HMRC, 2026-03-04
• GOV.UK: Customs Declaration Service — GOV.UK / HMRC, 2026-03-04