How do I fix BR-O-10?

Invoice Navigator automatically fixes this issue by correcting the `cac:TaxSubtotal` element in your Invoice (BR-O-10). You can also use Invoice Navigator's compliance engine to correct this automatically in your pipeline.

Is BR-O-10 a critical error?

Yes, BR-O-10 is a critical error that will cause invoice rejection. It must be fixed before submission.

Can BR-O-10 be automatically fixed?

Many instances of BR-O-10 can be automatically corrected using Invoice Navigator's compliance engine. The fix is applied in your pipeline with full audit evidence.

errorEN 16931

`BR-O-10`:This VAT category requires an exemption reason code or text explaining why...

This VAT category requires an exemption reason code or text explaining why no tax is charged (applies to `cac:TaxSubtotal`, rule BR-O-10).

Severity

Fatal

Rule set

EN 16931

Country

All EU

Fix type

AUTO-FIX

Confidence

90%

Engine Classification

Add VAT exemption reason code for Not subject to VAT breakdown per EN16931 BR-O-10

Confidence: 90% · Applied automatically in pipeline

What is BR-O-10?

BR-O-10 is a fatal validation rule defined in the EN 16931 specification. It validates the TaxExemptionReasonCode element under ID='O'] > TaxCategory in the UBL invoice XML.

When this rule fires, the invoice is non-compliant and will be rejected by Peppol access points and national validation services. The sending system receives a rejection response and the invoice does not reach the buyer.

Target path: //cac:TaxTotal/cac:TaxSubtotal[cac:TaxCategory/cbc:ID='O']/cac:TaxCategory/cbc:TaxExemptionReasonCode

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Why This Error Matters

Invoice will be rejected. "Not subject to VAT" (category O) has strict rules: no VAT identifiers allowed, no other categories permitted, and exemption reason required. Non-compliance prevents validation.

BR-O-10 is a hard failure. Invoices that trigger this rule are rejected at the access point and never reach the recipient. In Peppol networks, this means your sending system receives an MLR (Message Level Response) with a rejection status. The invoice must be corrected and re-sent, adding delay to your payment cycle.

Invoice Navigator can automatically correct this error in your pipeline. The fix is applied with full audit evidence, so your compliance trail remains intact.

Validator Behavior

·Causes invoice rejection
·Error returned: BR-O-10
·Specification: EN 16931

Before / After

Failing XML

<cac:TaxTotal>
  <!-- cac:TaxSubtotal is missing -->
</cac:TaxTotal>

Corrected XML

<cac:TaxTotal>
  <cac:TaxSubtotal>valid-value</cac:TaxSubtotal>
</cac:TaxTotal>

Technical Reference

XPath//cac:TaxTotal/cac:TaxSubtotal[cac:TaxCategory/cbc:ID='O']/cac:TaxCategory/cbc:TaxExemptionReasonCode

SpecEN 16931

Operationset_default

StrategyAdd VAT exemption reason code for Not subject to VAT breakdown per EN16931 BR-O-10

Common Causes

·Category O breakdown missing exemption reason code or text
·BT-121 or BT-120 required for "Not subject to VAT"
·O category needs exemption justification
·cbc:TaxExemptionReasonCode or TaxExemptionReason absent
·Out-of-scope treatment requires explicit reason

Seeing this in production? The API handles BR-O-10 automatically. See the fix response →

Related Errors

BR-45

Each VAT breakdown (BG-23) shall have a VAT category taxable amount (BT-116).

BR-48

Document allowance tax category required

BR-AE-09

Reverse charge VAT breakdown tax amount must be zero

Last updated: 27 February 2026

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Handle BR-O-10 Automatically in Your Pipeline

The compliance engine auto-remediates this error with controlled safety policies and evidence pack generation.

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BR-O-10:This VAT category requires an exemption reason code or text explaining why...