What causes the UBL-SR-06 error?

UBL dates must use YYYY-MM-DD format.

How do I fix UBL-SR-06?

Use ISO 8601 date format (YYYY-MM-DD). Invoice Navigator can propose a fix for this error, which you review and confirm before it is applied.

Is UBL-SR-06 a critical error?

Yes, UBL-SR-06 is a critical error that will cause invoice rejection. It must be fixed before submission.

Error codes · ubl-2.1

UBL-SR-06In your invoicing software

Preceding invoice reference shall occur maximum once

This is the rejection, word for word: „[UBL-SR-06] Your invoice contains multiple preceding invoice references. EN16931 allows only one preceding invoice reference.“

XPath: //cbc:IssueDate, //cbc:DueDate, etc.

What to have readyNothing. The file has to be re-exported from your invoicing software; we check it again afterwards.

What we doUse ISO 8601 date format (YYYY-MM-DD).

Choose the rejected invoiceor drop it here

XRechnung XML or ZUGFeRD PDF. Checking is free · corrected file €1.90 · the first every 30 days is free · no sign-up.

What the finding looks likeExample

FindingStructure invalid · UBL-SR-06

Location/Invoice/cac:BillingReference/cac:InvoiceDocumentReference

From youA re-exported file

ThenRe-export

ProofSHA-256 and /verify link after the check

Often appears together with

UBL-SR-07Preceding invoice number missing