The FatturaPA is an electronic invoice (Decree provided for by Italian Law number 633, 1972, article 21, subsection 1) and is the only type of invoice that will be accepted by Public Administrations which, according to the Law, are obliged to make use of the Exchange System.

The FatturaPA has the following characteristics:

• the content is structured, in an XML (eXtensible Markup Language) file, according to the FatturaPA format. This format is the only one accepted by the Exchange System,
• the authenticity of origin and the integrity of the content are guaranteed by the person who issues the invoice by affixing a certified electronic signature or a digital signature,
• the transmission is conditional on the presence of the unique identification code of the office to which the invoice is addressed, and which can be found in the Index of Public Administrations.

For the FatturaPA file signature, see the Sign the FatturaPA section.