To receive FatturaPA files from Economic Operators through the Exchange System, the Public Administration must first survey, in the Index of Public Administrations (IPA or PA Index), all its central and peripheral offices that may be addressees of electronic invoices.
The survey is carried out via the PA Index website. In particular, for electronic invoicing purposes, the Public Administration must provide, for each office likely to receive invoices, the identification data of the transmission channel previously registered with the Exchange System via the Register the channel application in the Tools section of this website.
It should be noted that if the CEM (Certified Electronic Mail) channel is used, it is not necessary to register in advance with the ES. The address must however be contained in the PA Index.
On conclusion of the survey of the addressee office, the IndicePA gives the Administration a six-digit alphanumeric Office Code, indispensable for receiving the invoices from the economic Operators (the Office Code corresponds to the CodiceDestinatario inside the FatturaPA file).
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