BR-1: Specification identifier missing (BT-24 / CustomizationID)
Every EN 16931-compliant invoice must include the specification identifier (BT-24). This field tells the receiving system which invoice profile is in use: Factur-X, Peppol BIS 3.0, XRechnung, ZUGFeRD, etc. Missing this field triggers BR-1.
Last updated: 2026-06-21
Affected field
BT-24 SpecificationIdentifier / cbc:CustomizationID (UBL) / ram:GuidelineSpecifiedDocumentContextParameter/ram:ID (CII)
Cause
The invoicing software does not include this element in its XML export, or outputs an unrecognised value. Some custom XML templates omit CustomizationID because it was not required by older format versions.
Fix
Add cbc:CustomizationID (UBL) or ram:GuidelineSpecifiedDocumentContextParameter/ram:ID (CII) with the correct profile URI. For Factur-X EN 16931 profile: 'urn:cen.eu:en16931:2017#compliant#urn:factur-x.eu:1p0:en16931'. For Peppol BIS 3.0: 'urn:cen.eu:en16931:2017#compliant#urn:fdc:peppol.eu:2017:poacc:billing:3.0'.
<ubl:Invoice> <!-- ERROR: cbc:CustomizationID missing --> <cbc:ID>INV-2026-001</cbc:ID> <cbc:IssueDate>2026-09-01</cbc:IssueDate> </ubl:Invoice>
<ubl:Invoice> <cbc:CustomizationID>urn:cen.eu:en16931:2017#compliant#urn:factur-x.eu:1p0:en16931</cbc:CustomizationID> <cbc:ID>INV-2026-001</cbc:ID> <cbc:IssueDate>2026-09-01</cbc:IssueDate> </ubl:Invoice>
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Frequently asked questions
Which CustomizationID value should I use for Factur-X?▼
The value depends on the profile: MINIMUM = 'urn:factur-x.eu:1p0:minimum', BASIC WL = 'urn:factur-x.eu:1p0:basicwl', EN 16931 = 'urn:cen.eu:en16931:2017#compliant#urn:factur-x.eu:1p0:en16931', EXTENDED = 'urn:cen.eu:en16931:2017#conformant#urn:factur-x.eu:1p0:extended'. Refer to the official Factur-X specification for the exact strings.
What value should I use for Peppol BIS 3.0?▼
For Peppol BIS Billing 3.0 in UBL: 'urn:cen.eu:en16931:2017#compliant#urn:fdc:peppol.eu:2017:poacc:billing:3.0'. In CII: append ':restricted:cii' to the same URI.
Is BR-1 the same as 'unknown profile' errors on invoicing portals?▼
Related but different. Portal errors about 'unknown profile' usually mean CustomizationID is present but the value is not in the portal's whitelist. BR-1 fires specifically when the field is absent entirely. Both require correcting BT-24.