What is electronic invoicing?
Starting January 1, 2019, we will all be dealing with the dreaded "e-invoices," as industry insiders call them. But what is electronic invoicing and how does it work? Electronic invoicing is a digital system for issuing, transmitting, and storing invoices that allows us to permanently eliminate paper and all the associated printing, shipping, and storage costs. Electronic invoicing radically changes the way we compile, send, receive, and store invoices. The format, called FatturaPA, is the path through which electronic invoices must be produced. It is a structured data flow in digital format with the same information content as a paper invoice, but written in XML. Today, electronic invoicing defines a single, standardized path thanks to the Revenue Agency's Exchange System (SdI). Electronic invoices are compiled using electronic invoicing software. They are digitally signed (via a qualified electronic signature) by the invoice issuer or their intermediary to guarantee their origin and content. The invoice issuer must then send it to the recipient via the Exchange System, which, by law, is the mandatory gateway for all electronic invoices issued to both public administrations and private individuals (we'll soon see the subtle differences). After automatic technical checks, the Exchange System delivers the document to the public administration or private entity to which it is addressed. The Exchange System therefore acts as a hub between interested parties and is responsible for verifying that the received document is formatted correctly and that the data entered is complete.

The SdI is a kind of postman! The System will send you the invoice once it has verified the technical requirements. All you need to do is import the electronic invoice into your software to save it. If you're really keen to save it manually, simply open the file with a suitable reader and save it. The invoicing procedure is always the same. Create the invoice and then, instead of printing it or saving it as a PDF to send via email, generate the invoice file in the FatturaPA XML format. The important difference between a B2B electronic invoice (between private individuals with VAT numbers), an invoice to the Public Administration, and one to consumers (B2C) is that the Exchange System uses different methods to determine who to send the electronic invoice to, depending on the recipient:

· Public Administration offices are identified by a unique 6-character Office Code that must be included on the invoice;
· Consumers: there is still a veil of mystery surrounding how they will be identified and where the electronic invoice will be delivered by the SdI (the most widely accepted hypothesis is that they are identified by their tax code and that the SdI will deliver it to the tax drawer).
· for B2B recipients (businesses, professionals, etc.) there are 2 sending methods:

1) PEC: the XML file contains the PEC address of the customer to which SdI will forward the invoice.
2) SdI recipient code: when the customer has an SdI accreditation code, this code must be used to send them the invoice.

For further information, consult the online guide on the Revenue Agency website.