errorEN 16931

BR-37:Each Document level charge (BG-21) shall have a Document level charge VAT...

Each Document level charge (BG-21) shall have a Document level charge VAT category code (BT-102). Check the `cac:AllowanceCharge` element in your invoice XML.

Severity
Fatal
Rule set
EN 16931
Country
All EU
Fix type
AUTO-FIX
Confidence
75%
Category
structural

Engine Classification

Add issue date to preceding invoice reference when missing

Confidence: 75% · Applied automatically in pipeline

What is BR-37?

BR-37 is a fatal validation rule defined in the EN 16931 specification. It validates the IssueDate element under InvoiceDocumentReference 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:BillingReference/cac:InvoiceDocumentReference/cbc:IssueDate

Why This Error Matters

Invoice rejected. VAT cannot be correctly calculated without knowing the tax category.

BR-37 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-37
  • ·Specification: EN 16931

How to Fix It

1.

Calculate base

Sum of line amounts with this tax category

2.

Add to subtotal

Set as TaxableAmount with currency

3.

Verify calculation

TaxAmount = TaxableAmount × Percent ÷ 100

Before / After

Failing XML
<Invoice>
  <!-- cac:AllowanceCharge is missing -->
</Invoice>
Corrected XML
<Invoice>
  <cac:AllowanceCharge>valid-value</cac:AllowanceCharge>
</Invoice>

Technical Reference

XPath//cac:BillingReference/cac:InvoiceDocumentReference/cbc:IssueDate
SpecEN 16931
Operationset_default
StrategyAdd issue date to preceding invoice reference when missing

Code Example

<cac:TaxSubtotal>
  <cbc:TaxableAmount currencyID="EUR">1000.00</cbc:TaxableAmount>
  <cbc:TaxAmount currencyID="EUR">210.00</cbc:TaxAmount>
</cac:TaxSubtotal>

Common Causes

  • ·Document charge missing VAT category assignment
  • ·TaxCategory/ID not mapped for charges
  • ·Charge created before tax category configured
  • ·Export template missing charge tax category field
  • ·VAT code lookup failed for charge

Seeing this in production? The API handles BR-37 automatically. See the fix response →

Commonly Seen In

All invoicing software

Frequently Asked Questions

Each TaxSubtotal must include TaxableAmount (the base for VAT calculation).

Add TaxableAmount to each TaxSubtotal. You can also use Invoice Navigator's automatic Fixer tool to correct this instantly.

Yes, BR-37 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-37 can be automatically corrected using Invoice Navigator's Fixer tool. Upload your invoice and the tool will identify and fix common issues, including tax subtotal taxable amount required.

BR-37 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-37 Automatically in Your Pipeline

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