Conservazione Sostitutiva: The Complete Guide to Italian E-Invoice Storage

Italy's mandatory e-invoicing system requires more than just sending and receiving FatturaPA invoices through the SDI. Every invoice — whether issued or received — must also be preserved in a legally compliant digital archive for 10 years. This is the conservazione sostitutiva obligation, and it catches many businesses off-guard.

This guide covers what the law requires, which storage solutions qualify, what changed in May 2026, and how to avoid the most common mistakes.

What Is Conservazione Sostitutiva?

Conservazione sostitutiva literally means "substitute preservation" — it is the process of digitally preserving documents in a way that gives them the same legal standing as paper originals. Under the Italian Codice dell'Amministrazione Digitale (CAD) and the Codice Civile, businesses are required to preserve their fiscal documents (including all invoices) for 10 years.

For FatturaPA invoices specifically, the obligation derives from:

Art. 39 DPR 633/72: Requires preservation of VAT-relevant documents
D.M. 17 giugno 2014: The Italian Ministerial Decree that defined the technical requirements for compliant digital preservation
AGID (Agenzia per l'Italia Digitale) accreditation standards for preservation systems

The Agenzia delle Entrate published updated technical specifications in May 2026 (Provvedimento del Direttore, 8 maggio 2026), clarifying cloud storage requirements and switching procedures.

The 10-Year Window: When Does It Start?

A common point of confusion: the 10-year period starts from the end of the fiscal year in which the invoice was issued, not from the invoice date.

Invoice Issued	Fiscal Year Ends	Retention Until
Any date in 2024	31 Dec 2024	31 Dec 2034
Any date in 2025	31 Dec 2025	31 Dec 2035
Any date in 2026	31 Dec 2026	31 Dec 2036

If you have received a tax audit notice for a specific year, those invoices cannot be deleted even if their 10-year period has technically expired.

What the Archive Must Guarantee

AGID standards require that a conservazione sostitutiva system guarantees four properties:

Authenticity: The invoice must be immutable from the moment of preservation — no modifications are possible
Integrity: The preserved file must be byte-identical to the SDI-validated original
Readability: The archive must remain readable and accessible for the full 10-year period (including after software changes)
Traceability: The system must maintain an audit trail showing when each document was archived and by whom

These properties are enforced through electronic signatures and time stamps applied to each archived document at the time of preservation.

What Changed in May 2026

The Agenzia delle Entrate's May 2026 updated specifications clarified several previously grey areas:

Cloud Storage Is Now Explicitly Approved

Cloud-based conservazione is valid, provided:

The cloud provider holds ISO 27001 certification
Data is stored on servers physically located within the EU (GDPR alignment)
The provider can issue an attestato di conservazione (conservation certificate) on demand

This explicitly rules out consumer cloud storage (Dropbox, Google Drive, Microsoft OneDrive personal) as compliant conservazione solutions.

Switching Providers Mid-Retention

If you change your conservazione provider, the old provider must transfer your complete archive to the new provider in an AGID-compliant format within 90 days of contract termination. Always check this clause before signing a conservazione contract — some providers make export difficult.

Cross-Border Invoice Storage

Invoices for intra-EU supplies (to non-Italian customers) that are NOT routed through SDI are also subject to the 10-year digital preservation requirement. However, these do not require an SDI-certified conservazione service — any CAD-compliant system works. This matters for Italian exporters who generate Peppol or PDF invoices for their EU customers alongside FatturaPA for domestic clients.

How Conservazione Actually Works in Practice

Most businesses never interact directly with conservazione — their invoicing software or intermediary handles it automatically. Here is what happens in the background:

FatturaPA invoice is validated and delivered by SDI
Your intermediary (or the Agenzia delle Entrate's own free service) applies an electronic signature and a qualified time stamp to the XML file
The signed and time-stamped file is stored in an AGID-certified archive
After each fiscal year closes, a Pacchetto di Archiviazione (PA) (archiving package) is generated — a signed bundle of all documents from that year
The PA is stored for 10 years from 31 December of the year covered

If you use Aruba, Fattura24, Zucchetti, or TeamSystem, steps 1–5 happen automatically with no action required on your part. If you use the Agenzia delle Entrate's free portal, the free conservazione service is included but you must explicitly activate it in your Fatture e Corrispettivi account.

Does the Agenzia delle Entrate's Free Portal Count?

Yes — the Agenzia delle Entrate provides a free conservazione sostitutiva service at the Fatture e Corrispettivi portal for invoices issued through that portal. It is legally compliant.

However, the Agenzia recommends switching to a private provider for volumes above 1,000 invoices per year, citing slower response times for archive retrieval requests at high volumes.

For sole traders and freelancers issuing fewer than 1,000 invoices annually, the free portal is a perfectly adequate solution.

Conservazione for Foreign Businesses with Italian VAT

If your non-Italian business has a Partita IVA and issues FatturaPA invoices through SDI, the conservazione obligation applies to you exactly as it does to Italian companies.

The most practical approach for foreign businesses:

Use an Italian fiscal intermediary (commercialista) who handles SDI submission and conservazione together — they confirm both obligations are covered
Use an international platform with Italian conservazione — Aruba and Fattura24 accept non-Italian business registrations and include conservazione in their plans

Do not assume that storing the XML files on your company server in Germany or France satisfies the Italian conservazione requirement. It does not.

Software That Handles Conservazione Automatically

Software	Conservazione Included	Notes
Aruba Fatturazione Elettronica	✅ Yes — all plans	Including the free tier
Fattura24	✅ Yes — all plans	Via Aruba infrastructure
Zucchetti	✅ Yes	Via Zucchetti's certified archive
TeamSystem	✅ Yes	Via TeamSystem Digital
Agenzia delle Entrate portal	✅ Yes — free	Recommended for <1,000 invoices/year
SAP S/4HANA with Italian module	✅ Via certified partner	Requires configuration

Common Mistakes to Avoid

Mistake 1: Assuming conservazione is automatic when it isn't The Agenzia delle Entrate portal includes conservazione, but only if you issued the invoice through the portal. If you submitted invoices via an API (e.g., your own system connecting to SDI directly), you need a separate conservazione setup.

Mistake 2: Storing XML files locally and calling it conservazione Saving the FatturaPA XML to a folder on your PC or server does not meet conservazione requirements. The archive must have immutability guarantees, qualified time stamps, and AGID-compliant certification — a local folder has none of these.

Mistake 3: Ignoring received invoices The conservazione obligation applies equally to invoices you receive, not just those you send. Your intermediary's service must cover both directions. Most software handles this automatically, but confirm it.

Mistake 4: Not checking the conservazione clause when switching software If you change your FatturaPA platform, ensure the old platform provides you with an AGID-compliant export of your existing archive, and confirm the new platform can import it. Losing access to your historic archive is a compliance failure even if you move to better software.