The EORI number of an economic operator established in the customs territory of the European Union shall be issued by the customs authority of the Member State where the economic operator is established. Economic operators not established in the customs territory of the Union shall be registered by the customs authority of the Member State where the economic operator is carrying out or is planning to carry out its first customs-related operation.In Estonia, the EORI number is issued by the Estonian Tax and Customs Board.One economic operator can have only one (valid) EORI number, and this unique number should be used in all customs-related activities on the territory of the European Union.