SDI Error Codes: What They Mean and How to Fix Them

The SDI (Sistema di Interscambio) validates every FatturaPA invoice before forwarding it to the recipient. When an invoice fails validation, SDI returns an error notification with a specific code. Knowing what these codes mean saves critical time — you have only five business days to correct and resubmit before you must start with a fresh invoice number.

How SDI Notifications Work

When you submit a FatturaPA invoice through SDI (directly or via an intermediary), the system returns one of four outcomes:

RC — Ricevuta di Consegna: Invoice delivered successfully to the recipient. The invoice is legally valid from this moment.

NS — Notifica di Scarto: Invoice rejected. SDI found errors and has not forwarded the invoice. You must correct and resubmit within 5 business days.

MC — Mancata Consegna: Invoice not yet delivered to recipient (temporary). SDI accepted the invoice but cannot reach the recipient's PEC or SDI endpoint. Delivered within 10 days or returned to sender.

AT — Attestazione Trasmissione: Attestation that the invoice was transmitted but could not be delivered (recipient not reachable after 10 days). Invoice is still legally valid.

Common Error Codes and Fixes

Error 00001 — Errore nell'indicazione del tipo di documento

Meaning: The document type code (TipoDocumento) is missing or invalid. Fix: Check the TipoDocumento field. Valid codes include TD01 (invoice), TD04 (credit note), TD05 (debit note), TD24 (deferred invoice), etc. Ensure the code matches the actual document type.

Error 00002 — Errore nella data

Meaning: The invoice date (Data) is missing, formatted incorrectly, or in the future. Fix: Confirm the date is in YYYY-MM-DD format. The date cannot be in the future. For deferred invoices (TD24), the date cannot be before the last day of the month in which the goods/services were delivered.

Error 00006 — Identificativo fiscale del cedente/prestatore non valido

Meaning: The seller's tax identifier (Partita IVA) is invalid or does not exist in the tax registry. Fix: Double-check the Partita IVA against the official Agenzia delle Entrate registry (telematici.agenziaentrate.gov.it). This is a frequent error when the vendor's ERP has outdated data.

Error 00007 — Identificativo fiscale del cessionario non valido

Meaning: The buyer's tax identifier is invalid. Fix: Verify the customer's Partita IVA or Codice Fiscale with the Agenzia delle Entrate. If invoicing a foreign company with Italian VAT registration, check the exact format required.

Error 00011 — La data della fattura non può essere successiva alla data di trasmissione

Meaning: Invoice date is later than the transmission date. Fix: The invoice date cannot be in the future. Adjust the invoice date or wait until after the invoice date to submit.

Error 00403 — Numero fattura duplicato

Meaning: An invoice with the same number already exists for this seller in the current year. Fix: This is a critical error. Check whether the original invoice was actually rejected (NS) or accepted (RC). If the first was accepted, you must create a credit note for the duplicate and reissue with a new number. If the first was rejected, you can reuse the number in your corrected submission.

Error 00422 — Il codice destinatario non è valido

Meaning: The recipient's SDI routing code (CodiceDestinatario) is not valid. Fix: Verify the 7-character CodiceDestinatario with your customer. If they use PEC, use the 7-character code "0000000" and populate the PEC field instead. Do not mix the two.

Error 00424 — Il documento contiene dati non corretti

Meaning: General data error — the XML structure is valid but business rule validation failed. Fix: Review the specific sub-code included with this error. Common causes include mismatched VAT amounts, incorrect tax codes, or payment terms not aligned with invoice type.

The 5-Day Rule

When SDI rejects an invoice (NS notification), you have 5 business days to correct the error and resubmit the same invoice number. If you miss this window, the original invoice number is considered cancelled and you must:

1. Create a new invoice with the next sequential number
2. Do not reuse the rejected invoice number for any purpose
3. Inform your customer that the new invoice number replaces the rejected one

Missing the 5-day window frequently creates reconciliation problems in accounting systems. Set up email or webhook alerts in your SDI intermediary platform to catch rejections immediately.

Prevention: Validate Before Submitting

The best approach to SDI errors is preventing them before submission. Use your intermediary's pre-validation feature, or validate the XML separately using:

• Agenzia delle Entrate validator: available on fatturapa.gov.it
• Assintel validator: free tool widely used in the Italian accounting community
• Your accounting software's built-in validator: most modern Italian invoicing tools validate before submission

A pre-submission validation run costs nothing and catches most errors before they become 5-day emergencies.