Step 1. Do not pay straight away. You have 10 working days from receiving the decision. Paying without an appeal = accepting the claims.
Step 2. Collect the primary documents. Contract, invoice, SWIFT confirmation, packing lists, correspondence with the supplier. Customs has to prove that the price is not genuine — but without your documents that is hard to do.
Step 3. File an administrative complaint. The form is free, but you must state: the decision number, the arguments why the valuation method was applied incorrectly, and the list of evidence. File it through your account on the customs portal or in person — with an acknowledgement of receipt.
Step 4. Request a meeting. A face-to-face conversation with the official often resolves the issue faster than the 3-month complaint review period.
Step 5. Prepare for court. If the complaint is rejected, you have 10 days to file a claim with the administrative court. This is where you need a lawyer with experience in customs disputes.
Timeframes: administrative appeal — up to 30 days; court — 2–6 months.