The Single Central American Declaration (DUCA for its acronym in Spanish) authorizes EU goods to pass through a single series of customs formalities before entering Panama, Costa Rica, Nicaragua, Honduras, El Salvador and Guatemala rather than for each country. In the case of system application failures, those countries will be implementing a provisional system. The provisional system will run until June 27, when the DUCA will begin to work in its entirety.

With the DUCA recently up and running, businessmen have reported a series of interconnection problems in the computer systems processing customs declarations, prompting the national customs authorities to implement contingency plan allowing operations to be migrated to a secondary data center in the case of a system failure. They will also allow the release of goods through manual controls and also manually collect data for the national Customs Systems using the form submitted by users.

The DUCA was implemented as part of the commitments made by the Secretariat for Central American Economic Integration (SIECA in Spanish) with the EU by signing an Association Agreement in 2012. The DUCA replaces three regional trade forms: the Central American Single Customs Form (Fauca for its acronym in Spanish), the Single Declaration for International Land Customs Transport (DUT for its acronym in Spanish) and the Declaration of National Goods (DUA or DM, both for their acronym in Spanish).