errorEN 16931

BR-CO-15:Tax exclusive amount calculation error

Invoice total amount with VAT (BT-112) = Invoice total amount without VAT (BT-109) + Invoice total VAT amount (BT-110).. This applies to the `cbc:TaxInclusiveAmount` element in the invoice XML.

Severity
Fatal
Rule set
EN 16931
Country
All EU
Fix type
AUTO-FIX
Confidence
90%
Category
calculation

Engine Classification

Recalculate TaxInclusiveAmount as TaxExclusiveAmount + TaxAmount

Confidence: 90% · Applied automatically in pipeline

What is BR-CO-15?

BR-CO-15 is a fatal validation rule defined in the EN 16931 specification. It validates the TaxInclusiveAmount element under LegalMonetaryTotal 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: /Invoice/cac:LegalMonetaryTotal/cbc:TaxInclusiveAmount

Why This Error Matters

Invoice rejected. The gross total is what the buyer pays - it must be mathematically correct.

BR-CO-15 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-CO-15
  • ·Specification: EN 16931

How to Fix It

1.

Start with lines

Sum of LineExtensionAmount

2.

Add charges

Add document-level AllowanceCharge where ChargeIndicator=true

3.

Subtract allowances

Subtract where ChargeIndicator=false

4.

Set result

Equals TaxExclusiveAmount

Before / After

Failing XML
<cac:LegalMonetaryTotal>
  <cbc:TaxInclusiveAmount>999.99</cbc:TaxInclusiveAmount>
  <!-- Does not match expected calculation -->
</cac:LegalMonetaryTotal>
Corrected XML
<cac:LegalMonetaryTotal>
  <cbc:TaxInclusiveAmount>100.00</cbc:TaxInclusiveAmount>
  <!-- Matches expected calculation -->
</cac:LegalMonetaryTotal>

Technical Reference

XPath/Invoice/cac:LegalMonetaryTotal/cbc:TaxInclusiveAmount
SpecEN 16931
Operationrecalculate
StrategyRecalculate TaxInclusiveAmount as TaxExclusiveAmount + TaxAmount

Code Example

<cac:LegalMonetaryTotal>
  <cbc:LineExtensionAmount currencyID="EUR">1000.00</cbc:LineExtensionAmount>
  <cbc:TaxExclusiveAmount currencyID="EUR">950.00</cbc:TaxExclusiveAmount>
  <!-- 1000 - 50 document allowance = 950 -->
</cac:LegalMonetaryTotal>

Common Causes

  • ·Tax inclusive amount calculation incorrect
  • ·BT-112 does not equal BT-109 + BT-110
  • ·TaxInclusiveAmount formula mismatch
  • ·Manual gross total override broke calculation
  • ·VAT amount changed without updating inclusive total

Seeing this in production? The API handles BR-CO-15 automatically. See the fix response →

Commonly Seen In

All invoicing software

Frequently Asked Questions

TaxExclusiveAmount must equal LineExtensionAmount + Document Charges - Document Allowances.

Verify TaxExclusiveAmount calculation. You can also use Invoice Navigator's automatic Fixer tool to correct this instantly.

Yes, BR-CO-15 is a critical error that will cause invoice rejection. It must be fixed before submission to ensure your invoice is accepted by the recipient's system.

Many instances of BR-CO-15 can be automatically corrected using Invoice Navigator's Fixer tool. Upload your invoice and the tool will identify and fix common issues, including tax exclusive amount calculation error.

BR-CO-15 is commonly seen in exports from All invoicing software. These software packages sometimes generate invoices that need adjustment to meet full compliance standards.

See Also

Related Errors

Last updated: 27 February 2026

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Handle BR-CO-15 Automatically in Your Pipeline

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