PEPPOL-EN16931-R111 — E-Invoice Validation Rule & Fix

Fixture ID: peppolLinePeriodOutside · XPath: /ubl:Invoice/cac:InvoiceLine[1]/cac:InvoicePeriod/cbc:EndDate

1. Why This Rule Triggers (Diagnostic Message)

Line 1 carries an invoice line period (BG-26) that must not end after the invoicing period ends: the line says 2026-08-31 and the document's invoicing period (BG-14) says 2026-07-31. Peppol requires every line period to fall within the document period. A line period that runs past the end of the invoicing period bills for a supply the document has just said it does not cover, which is how the same week gets invoiced twice — once at the end of this period and once at the start of the next. Core EN 16931 constrains each period internally (BR-29, BR-30) but never relates the two, so this is a genuine tightening and one that catches a real class of double billing. This is a Peppol BIS Billing 3.0 profile rule: it applies because profile is "peppol-bis-3". It does not apply to the en16931, xrechnung-ubl or xrechnung-cii profiles, whose validators will accept the same document.

2. How to Fix PEPPOL-EN16931-R111

Either move lines[0].period.endDate inside the document period, or widen invoicingPeriod.endDate to cover it. If the line genuinely belongs to another period, it belongs on another invoice.

3. Valid Code / Payload Example

"invoicingPeriod": { "startDate": "2026-07-01", "endDate": "2026-07-31" }, "lines": [{ "period": { "startDate": "2026-07-05", "endDate": "2026-07-20" } }]