An EUR.1 is valid in countries that are covered by a EU trade agreement. With an EUR.1 certificate, the importer in the country of destination is entitled to pay less import of even no import duties. AnEUR.1 certificate is only used for products of preferential origin.
The use of a EUR1 is not mandatory. Clients are interested in it, because it can involve a financial advantage. In some cases there is little difference between the general and preferential rate, making it hardly worth the effort to apply for a EUR.1 certificate. When the products of preferential origin in the shipment are of less value than EUR 6.000,- then an EUR.1 certificate is not used.