The application for authorisation must be made in writing. Formal application (with form 0281) Open the form "Application for authorisation to use inward processing (0281)" on the Customs website. Download the "Customs Authorisation Questionnaire Parts I to III and Part V" from the Customs website. (If you have an AEO Authorization as an "Authorized Economic Operator", this step is not required. You do not need to complete the questionnaire). Attach all required documents and send the application to the main customs office in whose district you keep your main accounts for customs purposes. Once the main customs office has successfully checked that all the requirements for participation in the procedure have been met, you will receive an authorization. The authorization clarifies the details of how the procedure is to be carried out. Simplified application (with customs declaration) If you meet the requirements for using the simplified procedure, you can submit the application as part of an electronic or written customs declaration. Electronic customs declaration: Submit an individual customs declaration for entry for inward processing (EZA-AV) electronically via the ATLAS customs software ("Automated Tariff and Local Customs Clearance System"). The customs office responsible will check your application. If the check is positive, you will receive a message via the ATLAS software with further details on the authorisation. This releases the goods into the procedure. Written customs declaration: Complete copies 6 and 8 of the Single Administrative Document. Hand over the documents to the customs office responsible. The authorisation is effected by the release of the goods for the procedure. You will receive a voucher copy of the authorisation for your records. If, for example, you also wish to process goods in another Member State, you must submit the application electronically via the European Commission's EU Trader Portal. The option of submitting the application in a simplified form does not apply in this case. More information on the so-called "cross-member state authorisation" can be found on the Customs website.