UBL-SR-36
EN 16931-1 layer: en16931
Checked against Peppol BIS Billing 3.0 2026.5
What does UBL-SR-36 mean? Invoice line period shall occur maximum once
Why did my invoice fail UBL-SR-36?
An invoice line may carry an Invoice line period (BG-26), the billing/delivery period for that line, expressed with a start date (BT-134) and end date (BT-135). EN 16931 allows at most one period per line, so cac:InvoicePeriod must not occur more than once inside a single cac:InvoiceLine.
Official rule text
Invoice line period shall occur maximum once
Common causes
- Two cac:InvoicePeriod elements on the same invoice line.
- A recurring-service template emits one period per month on a single line instead of separate lines.
- Both a delivery period and an invoicing period written as two InvoicePeriod blocks.
How do I fix it?
Keep one period per line: <cac:InvoicePeriod><cbc:StartDate>2026-06-01</cbc:StartDate><cbc:EndDate>2026-06-30</cbc:EndDate></cac:InvoicePeriod>; use separate lines for distinct periods.
Related rules
UBL-SR-01 · UBL-SR-02 · UBL-SR-03 · UBL-SR-04 · UBL-SR-05 · UBL-SR-06 · UBL-SR-07 · UBL-SR-08
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