How do I fix BR-S-09?

Invoice Navigator automatically fixes this issue by correcting the `cbc:TaxAmount` element in your Invoice (BR-S-09). You can also use Invoice Navigator's compliance engine to correct this automatically in your pipeline.

Is BR-S-09 a critical error?

Yes, BR-S-09 is a critical error that will cause invoice rejection. It must be fixed before submission.

Can BR-S-09 be automatically fixed?

Many instances of BR-S-09 can be automatically corrected using Invoice Navigator's compliance engine. The fix is applied in your pipeline with full audit evidence.

Which accounting software causes BR-S-09?

BR-S-09 is commonly seen in exports from All invoicing software. These packages sometimes generate invoices that need adjustment.

errorEN 16931

`BR-S-09`:VAT amount is calculated incorrectly

The VAT amount in the standard-rated breakdown does not match the taxable amount multiplied by the tax rate. For example, if the taxable amount is 1,000.00 and the rate is 21%, the VAT amount should be 210.00.

Severity

Fatal

Rule set

EN 16931

Country

All EU

Fix type

AUTO-FIX

Confidence

95%

Engine Classification

Recalculates the VAT amount as taxable amount × rate / 100

Confidence: 95% · Applied automatically in pipeline

What is BR-S-09?

BR-S-09 is a fatal validation rule defined in the EN 16931 specification. It validates the TaxAmount element under TaxSubtotal 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/cbc:TaxAmount

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Why This Error Matters

Invoice will be rejected. Standard rated VAT (category S) requires seller VAT registration, positive VAT rate, and correct tax calculations. Missing elements prevent tax compliance verification.

BR-S-09 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-S-09
·Specification: EN 16931

How to Fix It

Check the taxable amount

Find the TaxableAmount in the standard-rated VAT breakdown.

Multiply by the rate

The VAT amount should be: taxable amount × rate ÷ 100. For 21%: 1000.00 × 21 ÷ 100 = 210.00.

Update the tax amount

Set the TaxAmount to the calculated value. Round to 2 decimal places.

Before / After

Failing XML

<cac:TaxSubtotal>
  <cbc:TaxAmount>999.99</cbc:TaxAmount>
  <!-- Does not match expected calculation -->
</cac:TaxSubtotal>

Corrected XML

<cac:TaxSubtotal>
  <cbc:TaxAmount>100.00</cbc:TaxAmount>
  <!-- Matches expected calculation -->
</cac:TaxSubtotal>

Technical Reference

XPathcac:TaxTotal/cac:TaxSubtotal/cbc:TaxAmount

SpecEN 16931

Operationrecalculate

StrategyRecalculates the VAT amount as taxable amount × rate / 100

Common Causes

·Rounding error in tax calculation
·Tax rate changed without recalculating the amount
·ERP uses a different rounding method than EN16931

Seeing this in production? The API handles BR-S-09 automatically. See the fix response →

Commonly Seen In

All invoicing software

Related Errors

BR-CO-14

Tax subtotal taxable amount mismatch

BR-S-08

Standard rated VAT amount doesn't add up

Last updated: 27 February 2026

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Handle BR-S-09 Automatically in Your Pipeline

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

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BR-S-09:VAT amount is calculated incorrectly