PEPPOL-EN16931-R110 — E-Invoice Validation Rule & Fix

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

1. Why This Rule Triggers (Diagnostic Message)

Line 1 carries an invoice line period (BG-26) that must not begin before the invoicing period begins: the line says 2026-06-01 and the document's invoicing period (BG-14) says 2026-07-01. Peppol requires every line period to fall within the document period. A line period starting before the document period claims for time outside the window the invoice declares, and the buyer's accrual for the earlier period has already been closed against a different invoice. 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-R110

Either move lines[0].period.startDate inside the document period, or widen invoicingPeriod.startDate 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" } }]