UBL-SR-48: Each line needs exactly one VAT category
Each line needs exactly one VAT category; restore exactly one ClassifiedTaxCategory on the invoice line.
What the rule says
[UBL-SR-48]-Invoice lines shall have one and only one classified tax category.
Official en16931 source, version 1.3.16. EUPL 1.2; sources, licences and notices. Syntax and business checks are separate; this is not certification.
Each line needs exactly one VAT category
Each line needs exactly one VAT category. The controlled example changes the specific field or group named by this rule. Duplicate only /*/cac:InvoiceLine[1]/cac:Item/cac:ClassifiedTaxCategory.
Business terms: No explicit BT number in the official rule text; use the XML context below.
Restore exactly one ClassifiedTaxCategory on the invoice line.
Reproduced failure and correction
Tested on 2 November 2026 with the production SaxonC-HE 13.1 / saxonche 13.1.1 engine, en16931 mode, UBL. The XSD passes; the report then contains UBL-SR-48. Restoring this fragment makes the complete original invoice pass the selected checks.
[UBL-SR-48]-Invoice lines shall have one and only one classified tax category.Additional triggered rules: 0. None. Counts include distinct error and warning codes; the target code is excluded.
Precise mutated XPath: /*/cac:InvoiceLine[1]/cac:Item/cac:ClassifiedTaxCategory.
Before: triggers this rule
<cac:Item xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2" xmlns:ubl="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2" xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2">
<cbc:Description>Zeitschrift Inland</cbc:Description>
<cbc:Name>Zeitschrift [...]</cbc:Name>
<cac:SellersItemIdentification>
<cbc:ID>246</cbc:ID>
</cac:SellersItemIdentification>
<cac:CommodityClassification>
<cbc:ItemClassificationCode listID="IB">0721-880X</cbc:ItemClassificationCode>
</cac:CommodityClassification>
<cac:ClassifiedTaxCategory>
<cbc:ID>S</cbc:ID>
<cbc:Percent>21</cbc:Percent>
<cac:TaxScheme>
<cbc:ID>VAT</cbc:ID>
</cac:TaxScheme>
</cac:ClassifiedTaxCategory>
<cac:ClassifiedTaxCategory>
<cbc:ID>S</cbc:ID>
<cbc:Percent>21</cbc:Percent>
<cac:TaxScheme>
<cbc:ID>VAT</cbc:ID>
</cac:TaxScheme>
</cac:ClassifiedTaxCategory>
</cac:Item>
After: passes
<cac:Item xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2" xmlns:ubl="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2" xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2">
<cbc:Description>Zeitschrift Inland</cbc:Description>
<cbc:Name>Zeitschrift [...]</cbc:Name>
<cac:SellersItemIdentification>
<cbc:ID>246</cbc:ID>
</cac:SellersItemIdentification>
<cac:CommodityClassification>
<cbc:ItemClassificationCode listID="IB">0721-880X</cbc:ItemClassificationCode>
</cac:CommodityClassification>
<cac:ClassifiedTaxCategory>
<cbc:ID>S</cbc:ID>
<cbc:Percent>21</cbc:Percent>
<cac:TaxScheme>
<cbc:ID>VAT</cbc:ID>
</cac:TaxScheme>
</cac:ClassifiedTaxCategory>
</cac:Item>
The context shown is part of a complete invoice; it is not a standalone invoice. Mutation: duplicate at /*/cac:InvoiceLine[1]/cac:Item/cac:ClassifiedTaxCategory. The passing baseline is validated with the selected pinned package. UBL examples use a controlled single-line adaptation of the official XRechnung example; the CII example uses the official EN 16931 baseline.
Download complete failing invoice · Download complete passing invoice
Check the rest of the invoice
Repair the source data and exporter, then validate the complete invoice again with the same package. Review every remaining error and warning; a passing rule is not a guarantee of recipient acceptance.
EN 16931 syntax and business checks · XRechnung profile requirements · Pro/Team batch checks.