SDI-00200:Duplicate invoice number
Invoice number + year combination must be unique per sender. SDI maintains a registry and rejects duplicates within the same fiscal year.
Engine Classification
Financial or legal field · Modification blocked by policy
Reason: SDI maintains a registry of all submitted invoices. If this number+year combination was already accepted, you must generate a new unique invoice number in your ERP/accounting system. If the original was rejected for other reasons, fix those issues - the number itself is still available.
What is SDI-00200?
SDI-00200 is a fatal validation rule defined in the FatturaPA specification (ITA national rules). It checks whether duplicate invoice number.
When this rule fires, the invoice is non-compliant and will be rejected by Peppol access points and national validation services. The sending system receives a rejection response and the invoice does not reach the buyer.
Why This Error Matters
SDI-00200 is a hard failure. Invoices that trigger this rule are rejected at the access point and never reach the recipient. In Peppol networks, this means your sending system receives an MLR (Message Level Response) with a rejection status. The invoice must be corrected and re-sent, adding delay to your payment cycle.
Validator Behavior
- ·Causes invoice rejection
- ·Rejected by SDI (Sistema di Interscambio)
- ·Error returned: SDI-00200
- ·Specification: FatturaPA
How to Fix It
Technical Reference
Code Example
<Numero>2025-00123</Numero>Common Causes
- ·Invoice number already used this year
- ·Database restored with old numbering
- ·Multiple systems using same number series
Seeing this in production? The API handles SDI-00200 automatically. See the fix response →
Frequently Asked Questions
Invoice number + year combination must be unique per sender. SDI maintains a registry and rejects duplicates within the same fiscal year.
Ensure unique sequential numbering and include year in the invoice number. This error involves a protected field — Invoice Navigator flags it in your pipeline so your team can correct it at the source.
Yes, SDI-00200 is a critical error that will cause invoice rejection. It must be fixed before submission to ensure your invoice is accepted by the recipient's system.
SDI-00200 involves a financial or legal field that cannot be auto-modified by policy. Invoice Navigator detects and flags this error immediately, but the correction must be made manually in your ERP or invoicing software.
Related Content
Last updated: 3 March 2026
Detect SDI-00200 Before Submission
This error involves a financial or legal field that cannot be auto-modified. The compliance engine flags it immediately with a clear diagnosis so your team can fix it at the source.