Rules / PEPPOL-EN16931-F001 · Markdown
Peppol BIS Billing 3.0 · rule
PEPPOL-EN16931-F001
What does PEPPOL-EN16931-F001 mean? A date MUST be formatted YYYY-MM-DD.
Why did my invoice fail PEPPOL-EN16931-F001?
All dates in the invoice must be formatted as YYYY-MM-DD (ISO 8601 calendar date), with no time part or timezone. This applies to elements such as cbc:IssueDate, cbc:DueDate and cbc:ActualDeliveryDate and guarantees dates parse identically in every receiving system.
Official rule text
A date MUST be formatted YYYY-MM-DD.
Common causes
- Locale formats like DD.MM.YYYY or MM/DD/YYYY
- Appending a time or timezone (2026-07-18T00:00:00)
- Single-digit month or day without leading zero (2026-7-8)
How do I fix it?
<cbc:IssueDate>2026-07-18</cbc:IssueDate>
Check your invoice against this rule
Paste it into the live demo, or call POST /v1/validate. See the quickstart.