How do I fix BR-O-13?

Remove or correct the `cac:TaxSubtotal` element in your Invoice XML to comply with the rule (BR-O-13). You can also use Invoice Navigator's compliance engine to correct this automatically in your pipeline.

Is BR-O-13 a critical error?

Yes, BR-O-13 is a critical error that will cause invoice rejection. It must be fixed before submission.

Can BR-O-13 be automatically fixed?

Many instances of BR-O-13 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-13`:Inconsistent allowance VAT with "Not subject to VAT". Document allowances...

Inconsistent allowance VAT with "Not subject to VAT". Document allowances must use VAT category O when the invoice uses "Not subject to VAT".

Severity

Fatal

Rule set

EN 16931

Country

All EU

Fix type

BLOCKED

Engine Classification

Financial or legal field · Modification blocked by policy

What is BR-O-13?

BR-O-13 is a fatal validation rule defined in the EN 16931 specification. It checks whether inconsistent allowance vat with "not subject to vat". document allowances....

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.

This error requires manual correction — financial fields are protected by policy.Test This Error ↓

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-13 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.

Validator Behavior

·Causes invoice rejection
·Error returned: BR-O-13
·Specification: EN 16931

Before / After

Failing XML

<cac:TaxTotal>
  <cac:TaxSubtotal>-100.00</cac:TaxSubtotal>
</cac:TaxTotal>

Corrected XML

<cac:TaxTotal>
  <cac:TaxSubtotal>100.00</cac:TaxSubtotal>
</cac:TaxTotal>

Technical Reference

SpecEN 16931

Strategy1. Check VAT category consistency. 2. Ensure rates match categories. 3. Add missing identifiers.

Common Causes

·Invoice with O breakdown contains non-O category allowances
·Document allowance BT-95 is not O despite O breakdown
·Allowance VAT category inconsistent with invoice breakdown
·All allowances must use O when O breakdown exists
·Mixed allowance categories with out-of-scope breakdown

Seeing this in production? The API handles BR-O-13 automatically. See the fix response →

Related Errors

BR-32

Each Document level allowance (BG-20) shall have a Document level allowance...

BR-45

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

BR-48

Document allowance tax category required

Last updated: 27 February 2026

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Handle BR-O-13 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-13:Inconsistent allowance VAT with "Not subject to VAT". Document allowances...