As of January 1, 2024 for goods arriving by air, or March 1, 2024 for goods arriving by sea, the possibility of sending G3 (goods presentation notification) and G4 (temporary storage declaration) messages will be opened in the production environment.

This will mark the beginning of a period of coexistence during which it will be possible to choose between submitting the current summary declaration of temporary storage (DSDT) or sending the aforementioned G3 and G4 messages. This possibility will be extended, both in the air and maritime fields, until the application of Regulation (EU) 2019/1239 of the European Parliament and of the Council, of June 20, 2019, which creates a European one-stop environment single maritime (scheduled for August 15, 2025).

In the event that it is decided to send G3 and G4 messages during the coexistence period, it should be noted that:

• Before sending messages, it will be necessary to pass tests to ensure compliance with the functional limitations of the system, for which you will have to contact the AEAT Customs Applications User Service Center.
• Other documents, messages or statements linked to the sent messages, such as the G5 message (movement of goods in temporary storage) or certain G4 dating documents, will not be available initially. These limitations determine that, if you want to continue having the DSDT functionalities, you must continue using it until the communication of the integration of all services and declarations related to the G4 declaration.

Tax Agency: Technical guides - Presentation of the SAD (Single Administrative Document)