UBL-SR-16
EN 16931-1 layer: en16931
Checked against Peppol BIS Billing 3.0 2026.5
What does UBL-SR-16 mean? Buyer identifier shall occur maximum once
Why did my invoice fail UBL-SR-16?
The Buyer identifier (BT-46), which is the electronic identifier of the buyer under cac:AccountingCustomerParty/cac:Party/cac:PartyIdentification/cbc:ID, may be stated at most once on an invoice. EN 16931 models BT-46 as a single 0..1 term, so a buyer can only be given one such identifier.
Official rule text
Buyer identifier shall occur maximum once
Common causes
- A mapping loop emits cbc:ID for every buyer identifier stored in the source system (e.g. an internal customer number and a GLN).
- Both a scheme-qualified and an unqualified PartyIdentification/ID are written for the same buyer.
- Merging two data sources duplicates the buyer identification element.
How do I fix it?
Keep a single identifier: <cac:PartyIdentification><cbc:ID schemeID="0088">7300010000001</cbc:ID></cac:PartyIdentification> and remove any additional cac:PartyIdentification blocks under AccountingCustomerParty/Party.
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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