OasisPro · Italy SDI eInvoicing · FatturaPA · EU eInvoicing Gateway · 2026
Italy SDI eInvoicing.
The original EU mandate. Still tripping up businesses in 2026.
Italy SDI eInvoicing has been mandatory for all Italian B2B and B2G transactions since January 2019, making it the oldest and most established national eInvoicing mandate in the EU. Yet seven years on, Italy SDI eInvoicing still generates more compliance failures, more rejected invoices, and more operational confusion for non-Italian businesses than almost any other EU country mandate. Here is exactly what FatturaPA and the SDI system require, who it applies to, and how any ERP connects to it through one gateway.
The confusion is understandable.
Italy SDI eInvoicing operates through a national clearance model with its own XML format, its own submission hub, and its own validation rules that are more demanding than those in newer EU mandates.
Businesses that succeed with Peppol-based mandates in Belgium or Germany still find Italy SDI requires a different approach.
This guide covers how the SDI system works, what FatturaPA requires, and who is in scope.
It also covers the OasisPro EU eInvoicing Gateway and how it connects any ERP to Italy SDI through one affordable middleware connection.
Italy SDI eInvoicing is not Peppol. It is a clearance model with its own XML format, its own hub, and its own strict validation that rejects non-compliant invoices before they reach the recipient.
Understanding the difference between Italy SDI and Peppol-based mandates is the most important step for any business setting up eInvoicing with Italian trading partners. The OasisPro EU eInvoicing Gateway handles both models through one connection, converting your ERP output to FatturaPA, submitting to SDI, tracking status, and handling the SDI response lifecycle automatically.
What Italy SDI eInvoicing actually is: the clearance model explained
Italy SDI eInvoicing operates as a clearance model.
Every invoice involving an Italian VAT-registered entity must pass through the Sistema di Interscambio, the SDI hub operated by the Italian tax authority Agenzia delle Entrate, before it reaches the recipient.
This is fundamentally different from Peppol-based decentralised models.
In Peppol (used by Belgium, Germany, and soon Slovakia), invoices travel directly between certified access points without central tax authority intervention.
In Italy SDI, the tax authority sits in the middle of every transaction, validates the invoice against FatturaPA rules, and either delivers it or rejects it.
The Agenzia delle Entrate SDI portal is the authoritative source for FatturaPA technical specifications and mandate updates.
The format has been updated multiple times since 2019, and businesses relying on static ERP integrations that do not track Italian specification updates discover non-compliance when invoices start being rejected.
Italy SDI eInvoicing does not just route invoices. It validates them. Non-compliant FatturaPA invoices are rejected by SDI before the recipient ever sees them.
This is the key difference from PDF-based or Peppol-based invoicing. In a clearance model, a rejected invoice is not merely an inconvenience. It means the customer has not legally received an invoice, which has cash flow, audit, and VAT reclaim implications. The SDI rejection must be resolved and a corrected invoice resubmitted before the transaction can proceed.
Who Italy SDI eInvoicing applies to in 2026
The scope of Italy SDI eInvoicing has expanded since its 2019 launch. The mandate originally covered resident Italian businesses and has progressively extended to cover more transaction types and non-resident entities.
| Business type | In scope for Italy SDI | Since when |
|---|---|---|
| Italian resident businesses, all B2B | Yes, fully mandatory | January 2019 |
| Italian resident businesses, B2G (government) | Yes, fully mandatory | March 2015 (earlier than B2B) |
| Non-resident businesses with Italian VAT registration | Yes, mandatory | July 2022 |
| Non-resident businesses without Italian VAT, selling to Italian B2B | Esterometro applies | Reporting obligation, not SDI submission |
| Non-resident businesses, B2C sales to Italian consumers | Not in scope | SDI not required for B2C |
What FatturaPA requires: the Italy SDI eInvoicing format explained
FatturaPA is Italy's structured XML invoice format for SDI submission. It is not the same as UBL 2.1 or EN 16931, the formats used in Peppol-based mandates.
FatturaPA has its own schema, its own mandatory fields, and its own validation rules enforced by the SDI hub.
Codice Destinatario or PEC address
Every FatturaPA invoice requires either the recipient's 7-character Codice Destinatario (SDI routing code) or their certified email address (PEC). Without the correct routing identifier, the SDI hub cannot deliver the invoice. This information must be obtained from the Italian customer before invoicing.
Italian VAT number (Partita IVA)
The supplier's Italian VAT number (Partita IVA) must be correctly populated in the FatturaPA header. Non-resident businesses with Italian VAT registrations must use the correct format. Errors in the Partita IVA field cause immediate SDI rejection.
Progressive invoice numbering
FatturaPA requires a progressive numbering system within each calendar year. Gaps in the sequence raise questions from the Agenzia delle Entrate. Invoice numbers must be unique within the VAT registration's submission history on SDI.
VAT and tax regime codes
FatturaPA includes mandatory fields for Italian VAT codes, tax regime identifiers (Regime Fiscale), and the nature of the transaction. These codes are Italian-specific and do not map directly from standard ERP VAT code configurations without transformation.
Digital signature requirement
FatturaPA invoices submitted to SDI must be digitally signed with a qualified electronic signature or processed through an accredited intermediary. Most businesses use an accredited SDI intermediary (like the OasisPro EU eInvoicing Gateway) rather than managing digital signing infrastructure themselves.
SDI response lifecycle management
After submission, SDI returns one of six response codes: RC (delivered), MC (cannot deliver), NS (rejected), DT (expired), AT (certificate attestation), or SO (rejected, no alternative). Each requires a different operational response. This lifecycle must be tracked and managed automatically.
Italy SDI eInvoicing is not a format change. It is a complete change in how invoice exchange works for any business with Italian B2B trading relationships.
Why Italy SDI eInvoicing still catches businesses out in 2026
Seven years after the mandate launched, Italy SDI eInvoicing still generates a surprising volume of compliance failures for non-Italian businesses. The reasons are consistent across the businesses OasisPro speaks to.
Codice Destinatario not collected at customer onboarding
The most common single failure point. Businesses set up new Italian customers without collecting the Codice Destinatario or PEC address. Without these, invoices cannot be routed through SDI. The discovery happens when the first invoice is attempted, often weeks after the customer relationship has started.
Static ERP integration not tracking FatturaPA spec updates
Italy has updated the FatturaPA technical specification multiple times since 2019. ERP integrations built to the original 2019 spec may generate invoices that fail newer SDI validation rules. Without a middleware provider maintaining the integration against current specifications, rejection rates increase with each Italian update.
SDI response codes not monitored
Many businesses submit FatturaPA invoices and do not systematically monitor SDI responses. MC (cannot deliver) and NS (rejected) responses require action before the invoice is legally considered delivered. Unmonitored rejections delay cash collection and create VAT compliance gaps.
Italian VAT code and tax regime mismatches
Standard ERP VAT configurations do not map cleanly to Italian Regime Fiscale and Natura codes required in FatturaPA. Without middleware that handles this transformation, FatturaPA invoices contain incorrect or missing Italian tax fields that cause SDI validation failure.
Italy SDI eInvoicing and ViDA: how the two interact
Italy SDI eInvoicing predates ViDA and will continue to operate as Italy's domestic eInvoicing system after ViDA's Digital Reporting Requirements go live in July 2030. The two systems will coexist.
Under ViDA, Italy's SDI system must align with EU-wide standards by 2035.
The Italian tax authority is already involved in EU-level discussions about how SDI evolves toward the EN 16931 and Peppol infrastructure that ViDA uses for cross-border transactions.
For businesses connecting to Italy SDI now, a well-maintained gateway connection through a provider tracking Italian and EU-level developments is the most future-proof approach.
Building a direct point-to-point SDI integration today that does not adapt to Italian specification updates or ViDA harmonisation requirements will create technical debt.
The OasisPro EU eInvoicing Gateway covers Italy SDI alongside every other active EU mandate through one connection.
One middleware connection from any ERP covers Italy SDI (FatturaPA), Belgium Peppol, France PDPs, Poland KSeF, Germany XRechnung, Romania e-Factura, and every other active EU country mandate. OasisPro maintains the gateway against current specifications for every country, including Italian FatturaPA updates, so your business stays compliant without rebuilding your ERP integration every time a country updates its format.
Read about the OasisPro EU eInvoicing GatewayConnecting your ERP to Italy SDI eInvoicing: what the process involves
- Collect Codice Destinatario from every Italian B2B customer. This is a prerequisite that must be addressed in your customer onboarding process. Without it, SDI cannot route invoices to the recipient.
- Map your ERP VAT codes to Italian Natura and Regime Fiscale codes. Italian-specific tax codes do not exist natively in most ERPs. Middleware must handle this transformation as part of FatturaPA generation.
- Ensure your FatturaPA generation tracks current Italian specifications. Static integrations built to older specs will generate rejections as Italy updates its format requirements. A maintained gateway provider handles this automatically.
- Implement SDI response monitoring. Every submitted invoice needs its SDI response tracked and acted on. MC and NS responses require corrected invoice resubmission. This cannot be a manual process at any meaningful invoice volume.
- Connect through an accredited SDI intermediary. Italy requires that FatturaPA invoices be submitted through the SDI hub by an accredited intermediary or directly with a qualified digital signature. The OasisPro EU eInvoicing Gateway operates as an accredited intermediary, removing the need for your business to manage signing infrastructure.
Any ERP. Italy SDI eInvoicing. One connection. Done.
The OasisPro EU eInvoicing Gateway connects your ERP to Italy SDI alongside every other active EU eInvoicing mandate. Talk to us about your Italian trading footprint and we will show you exactly what one connection covers.
What is Italy SDI eInvoicing?
Italy SDI eInvoicing is the mandatory electronic invoicing system operated by the Italian tax authority (Agenzia delle Entrate). SDI stands for Sistema di Interscambio, the central clearance hub that validates and routes FatturaPA XML invoices between suppliers and customers. Every B2B invoice involving an Italian VAT-registered entity must pass through SDI before it reaches the recipient. The mandate has been in force since January 2019.
Does Italy SDI apply to non-Italian businesses?
Yes. Non-resident businesses with an Italian VAT registration have been in scope for Italy SDI eInvoicing since July 2022. Any business that issues invoices to Italian B2B customers where the customer has an Italian VAT number and the transaction involves Italian VAT must use the FatturaPA format submitted via SDI. Non-resident businesses without Italian VAT registration but selling to Italian B2B customers are subject to the Esterometro cross-border reporting obligation instead.
What is the Codice Destinatario and why does it matter?
The Codice Destinatario is the 7-character SDI routing code that identifies where the Sistema di Interscambio should deliver an invoice to the recipient. Without it, SDI cannot route the invoice. Businesses must collect the Codice Destinatario from every Italian B2B customer before issuing invoices. If a customer does not provide one, their certified email address (PEC) can be used instead, but both are required at the point of invoice submission.
How does the OasisPro EU eInvoicing Gateway handle Italy SDI?
The OasisPro EU eInvoicing Gateway connects any ERP to Italy SDI through one middleware connection. It handles FatturaPA format generation from your ERP data, applies the required Italian VAT and tax regime code mappings, submits invoices to SDI through an accredited intermediary connection, tracks SDI response codes, and alerts your team when action is required. Italy SDI is covered alongside every other active EU country mandate through the same single gateway connection.
Italy SDI eInvoicing. Mandatory since 2019. The OasisPro EU eInvoicing Gateway connects any ERP in days.
Italy SDI eInvoicing is the most established and most exacting country mandate in the EU.
The combination of clearance model operation, FatturaPA-specific format requirements, and SDI response lifecycle management is demanding.
Businesses without a well-maintained gateway connection face recurring compliance issues regardless of how long the Italy SDI mandate has been in force.
The OasisPro EU eInvoicing Gateway handles Italy SDI alongside every other active EU mandate through one affordable connection. Talk to us about your Italian trading footprint.