Frequently Asked Question

Every invoice has a unique SDC Invoice Number. It is important for distinguishing all invoices in the database and can be used for investigation purposes. The unique SDC Invoice Number identifies:

• The taxpayer who issued the invoice
• The business location where it was issued
• The verification service (SDC) which checked and signed the invoice
• Whether there are any invoices issued with the same secure element, that are missing in the tax authority database

The SDC invoice number is created in a way that prevents taxpayers/cashiers to modify it in any way.

How is it created?

A fiscal invoice is created in two steps – Invoice Request and Invoice Response.

1. Invoice Request is sent by an Accredited POS to an SDC service. It contains the unique identifier (UID) of the taxpayer's secure element.
2. Invoice Response is generated by either a V-SDC or an E-SDC after data validation, and returned to the taxpayer's POS. Among other information, it contains the unique identifier (UID) of the secure element, which was used to digitally sign the invoice, as well as the counter number.

Elements of an SDC invoice number

Typically SDC invoice number looks like this:

7AF4D923-E3B30A31-234

• 7AF4D923 - the UID of the secure element which requested the signing.
• E3B30A31 - the UID of the secure element which signed (fiscalized) the invoice.
• 234 - corresponds to the total number of fiscal invoices issued with this combination of secure element UIDs