Even the most detail-oriented professionals make mistakes. A typo in the client's address, the wrong VAT rate, or an incorrect total amount can make an invoice legally invalid in Germany.
However, under German tax law (§ 14 UStG) and digital accounting principles (GoBD), you cannot simply open the old file, change the details, and re-save it. With the mandatory use of structured e-invoices (E-Rechnung) in 2026, manual corrections are technically impossible and legally dangerous.
1. The Core GoBD Rule: Never Delete Invoices
In German accounting, documents must be unalterable and fully traceable.
- Once an invoice is finalized and sent to a client, it cannot be deleted or modified.
- Deleting it creates a gap in your sequential invoice numbering, triggering immediate suspicions of tax evasion during an audit.
- The only legal way to fix a sent invoice is to issue an official cancellation document (Stornorechnung).
2. How to Issue a Stornorechnung
A Stornorechnung completely neutralizes the incorrect document by mirroring it with negative amounts.
Step 1: Create the Storno Issue a new document titled "Stornorechnung" with its own unique invoice number.
Step 2: Use Negative Amounts Copy all items from the original invoice but make the amounts (Net, VAT, Gross) negative (e.g., -100.00 €). This zeroes out the client's debt.
Step 3: Reference the Original You must explicitly mention the original incorrect invoice number and its issue date on the Stornorechnung.
Step 4: Issue a New Invoice Create a brand new invoice with the corrected data and a new sequential number.
(If you need a reliable visual structure for these documents, you can Solobuch platform designed for German compliance).
3. Canceling E-Invoices in 2026 (ZUGFeRD/XRechnung)
In 2026, correcting a B2B invoice is a highly technical process.
When creating a structured e-invoice, the XML data uses specific Document Type Codes. A standard invoice is code 380. A cancellation invoice (Credit Note) MUST use code 381. If you send a standard invoice with negative amounts, your client's ERP system will reject it.
To ensure your cancellation file has the perfect XML syntax before sending it, you can instantly use our ZUGFeRD Validator.
4. Automate the Correction
Instead of calculating negative amounts and struggling with XML codes, let our platform handle it. With one click on "Stornieren" (Cancel), you can neutralize the old document and automatically create an e-invoice with the corrected data in seconds.
Key Takeaways
- Never delete or overwrite an invoice that has already been issued.
- Use a Stornorechnung with negative amounts to zero out the mistake.
- Always reference the original invoice number on the cancellation document.
- Use automated software to ensure correct XML coding (Code 381) for e-invoices in 2026.
