Compliant storage of e-invoices: who must keep them, for how long, and what stays viewable online

Marta, a plumber in Verona, needs to prove in 2027 that she invoiced a customer €4,800 for a heating system installed in 2024. She logs into the Revenue Agency portal expecting to find the XML file where she had always seen it. It is gone; only a handful of summary data remain. She had not been careless. She had mistaken a temporary display for a legal archive.

An obligation shared by both parties

Every electronic invoice has two parties, and Italian law treats them alike. Article 39 of Presidential Decree 633/1972, which the Agency's guide refers to, requires compliant storage from the business issuing the document and from the business receiving it. Neither can rely on the other side's archive to satisfy its own duty.

The usual shortcut is to think that passing through the Exchange System, the SdI, is enough. The SdI checks, delivers and logs the file, but it does not take over the taxpayer's duty. Its job is to move the invoice from one party to the other, not to look after it for years on anyone's behalf.

The practical consequence is easy to state. Every sales invoice sent and every purchase invoice received through the SdI must end up, sooner or later, in a storage system. A sole trader who issues a hundred invoices a year and receives two hundred has three hundred documents to store, not one hundred.

The Agency's guide sets out three guarantees that compliant storage must provide over the years: invoices are never lost, they can always be read, and the original can be retrieved at any moment. A folder on a laptop delivers none of them. Laptops break, files get deleted, and old formats can become unreadable.

The service is usually sold by certified private providers. Alongside them, the Agency offers a free service covering all the electronic invoices a VAT-registered business issues and receives, available from the reserved area of its Fatture e Corrispettivi portal. The second module of this course is entirely devoted to that public service.

Viewing is not storing

The Fatture e Corrispettivi portal has a panel called Consultazione. Through its link to electronic invoices and other VAT data, a business sees every invoice and credit or debit note that went through the SdI correctly, whether issued, received or left available for collection. That convenience is precisely what makes it misleading.

The Agency draws the line between the two functions carefully. Viewing supports day-to-day administration in the period close to issue or receipt: checking an invoice against an order, booking it, following up a payment or preparing one. You can display the document and download a certified copy of the file.

Storage has another purpose. It archives the original file securely, under CAD rules, so that it is never mislaid or destroyed and can be recovered many years later. The Agency's own illustration is litigation, when a court needs the original invoice rather than a copy printed from a screen.

The two deadlines of online viewing

The page on the viewing service sets two horizons. Invoice files correctly transmitted to the SdI stay available in the reserved area until 31 December of the second calendar year following their receipt by the SdI. After that date the XML file can no longer be downloaded from the portal.

Something does survive: the so-called invoice data, meaning the document's summary fields. They remain viewable until 31 December of the eighth year following the year in which the related tax return was filed. Number, date, counterparty, taxable amount and VAT therefore outlive the complete file by several years.

The two clocks start from different events, and that is where mistakes happen. The file's clock starts with the year the SdI received it; the summary data's clock starts with the year the related return is filed. For an invoice dated 2024, the return is filed in 2025, so the eighth following year is 2033.

Marta's mistake is widespread because, for a little over two years, the viewing service looks like a complete archive. Anyone who has never needed an old invoice does not notice the limit. It surfaces on the day a customer disputes a bill, a bank asks for a document or the tax authorities open an audit.

How long an invoice may be needed

The viewing window must not be confused with the period during which an invoice may be asked for. The deadline for the authorities to serve a tax assessment notice is five years under the ordinary rules, as the page on the flat-rate scheme points out. A document can therefore matter well beyond the portal's two years.

The same page describes a reward for flat-rate taxpayers whose turnover consists exclusively of electronic invoices: their assessment deadline drops to four years. It is a genuine advantage, but it does not shrink the life of a document to two years. Four years is still double the viewing window of the portal.

Civil law adds its own layer. The Agency's answers to frequent questions cite Article 2220 of the Civil Code, which governs how long a business keeps its records and documents, and confirm that the free public service complies with that rule too. This course does not quote the civil-law period: it should be read in the article itself.

The practical picture looks like this: two years of downloadable file, several more years of exposure to audits, a civil-law retention period of its own, and fifteen years of storage offered by the public service. Joining a storage service covers all of these horizons at once, instead of chasing each of them separately.

An audit, moreover, does not only look at the year just closed. It can cover periods several years back, when the file has long left the viewing service. At that point the only full evidence of the transaction is the stored original: summary data prove that an invoice existed, not what it actually said.

Private disputes work the same way. A contested warranty, a debt collection or a lawsuit with a customer or supplier may require the original invoice years later. A business with compliant storage produces it without argument; a business holding only a printout or a copy saved elsewhere invites challenges to its authenticity.

Finally, there is the plain matter of organisation. An archive that feeds itself, without anyone having to remember to copy files, is the only kind that stays complete over the years. Gaps nearly always come from a forgotten manual step: a month on holiday, a new assistant, a replaced computer.

Mixed situations: paper, flat-rate taxpayers, private customers

Not every invoice a business handles is electronic. Cross-border transactions and documents received outside the SdI can still produce paper invoices. The Agency's answers make clear that separate sub-ledgers are not required: electronic storage, compulsory for e-invoices, can sit alongside paper storage for the others.

Numbering can stay in a single sequence too. Invoice number 1 may be on paper and numbers 2 and 3 electronic, provided each document remains uniquely identifiable. What does not change is the Article 39 rule: an invoice born electronic is stored electronically, never printed out and filed in a binder.

Flat-rate taxpayers are not exempt from everything. Among the duties their scheme leaves in place, the Agency's page lists two concerning purchases, numbering and keeping the invoices received and the customs bills, as well as issuing and receiving e-invoices for domestic transactions. Purchase invoices arriving through the SdI must be stored by them as well.

A private consumer, on the other hand, has none of these duties. When asking for an invoice, the consumer need not provide a certified email address or handle an XML file: the seller or professional issues the e-invoice through the SdI and hands over a copy, on paper or in digital form, which is fully valid.

Private individuals can still look up the invoices addressed to them in their own reserved area, logging in with SPID, CIE or CNS. They cannot delegate that service to an intermediary, a restriction agreed between the Agency and the Data Protection Authority. The same viewing time limits apply to them as to businesses.

A routine that prevents surprises

The simplest way to avoid Marta's situation is to decide once and for all where invoices go. A business that already has accounting software, or an accountant offering storage, should check that the service is actually switched on and covers both the invoices it issues and those it receives.

A business with nothing in place can join the Agency's free service, the minimum solution covering every invoice that went through the SdI. Either way, it is worth writing down the start date and the scope covered, because those are the two facts you need on the day you go looking for an old document.

• Check once a year that the storage service is active and actually receiving documents
• Make sure purchase invoices reach storage, not just sales invoices
• Keep the few remaining paper invoices separate and in order
• Before 31 December, download any expiring files that do not appear to be stored
• Record the SdI identifier of important invoices so that a targeted search finds them

The last point deserves a word of explanation. Every file received by the SdI carries a unique identifier, the IdSdI, and the viewing service lets you search for an invoice by that number through its SdI/file search. Noting it next to high-value invoices means finding them again in seconds.