Customs knowledge base
Every term from day-to-day customs work, explained by people who file declarations themselves. Grouped by theme, so one term leads to the next.
Incoterms
Incoterms determine who arranges the transport, who bears the costs and where the risk passes. They appear on virtually every commercial invoice and help determine what belongs in the customs value. Every term from Incoterms 2020 is explained here, with what it means for the declaration.
View the termsDuties and taxes
Import duty, import VAT, excise duty and anti-dumping duty all come together in one amount at the bottom of the declaration. Which charge applies follows from the goods code, the origin and the value. These terms explain how that amount comes about and where it goes wrong.
View the termsGoods codes
The goods code determines the rate, the authorisation requirement and the chance of an inspection. One digit wrong and the whole declaration follows the wrong rules. This is where you find how HS, CN and TARIC relate to each other and how you arrive at the right classification.
View the termsDangerous goods
Dangerous goods touch the declaration through authorisations, prohibitions and restrictions attached to the goods code, and through the transport rules in ADR, IMDG and IATA. These terms connect the chemical classification to what Customs wants to see.
View the termsDocuments
A customs file is ultimately a stack of documents that have to match each other. Invoice, packing list, transport document, certificate: every field that deviates is a reason for a control. Here you find, per document, what belongs on it and why.
View the termsInspections
Fresh and veterinary products only enter the EU after pre-notification and inspection. TRACES-NT, the CHED and the NVWA set the pace, and a missed notification costs a day of shelf life. These terms explain the inspection chain.
View the termsDeclarations and procedures
Import, export, transit, warehousing, processing: every procedure has its own declaration type, its own data set and its own time limit. This is the largest group in the knowledge base and the place where DMS, NCTS and the UCC come together.
View the termsCustoms clearance
Customs clearance is the moment at which goods from a third country enter free circulation. What it costs, how long it takes and who is liable is explained here, term by term.
View the termsAuthorisations
Almost every simplification in the customs process hangs on an authorisation. AEO, customs warehousing, processing, comprehensive guarantee, article 23: these terms explain what each authorisation delivers and what you have to demonstrate for it.
View the termsSystems and parties
DMS, NCTS, DECO, TRACES-NT, Portbase, the DTV: the Dutch customs chain is a collection of systems that each want their own data. Here you find what each system does and which party is responsible for what.
View the termsValue and origin
Customs value and origin, together with the goods code, determine what you pay. Both are subject to control afterwards, because both are a calculation and not a fixed given. These terms explain how you substantiate them.
View the termsE-commerce
Small consignments in high numbers call for their own handling. DECO, IOSS and the H7 declaration make that possible, within limits that have shifted considerably since 2021. Here you find what applies below one hundred and fifty euro.
View the termsDMS and NCTS error codes
This page holds every official DMS error code from table A99, plus the NCTS error messages from the Codeboek Sagitta, part Transit. The code names the element or the situation, not the cause. The official Dutch wording is the source of truth. Source: edition 29 August 2026.
View the terms