errorEN 16931

`BR-45`:Each VAT breakdown (BG-23) shall have a VAT category taxable amount (BT-116).

Each VAT breakdown (BG-23) shall have a VAT category taxable amount (BT-116).. Check the `cac:TaxSubtotal` element in your invoice XML.

Severity

Fatal

Rule set

EN 16931

Country

All EU

Fix type

BLOCKED

Engine Classification

Financial or legal field · Modification blocked by policy

Reason: Billing period for service lines affects revenue recognition and tax treatment. Must be set according to service delivery terms.

What is BR-45?

BR-45 is a fatal validation rule defined in the EN 16931 specification. It validates the InvoicePeriod element under Invoice > InvoiceLine 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: XPath: /Invoice/cac:InvoiceLine/cac:InvoicePeriod

This error requires manual correction — financial fields are protected by policy.Get API Access

Why This Error Matters

Invoice rejected. Cannot verify VAT calculation without knowing the taxable base.

BR-45 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-45
·Specification: EN 16931

How to Fix It

Add period

InvoicePeriod with StartDate and EndDate

Format dates

YYYY-MM-DD format

Optional on header

Or add to document-level InvoicePeriod

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

XPathXPath: /Invoice/cac:InvoiceLine/cac:InvoicePeriod

SpecEN 16931

StrategyBLOCKED: This is a tax base amount. We cannot calculate taxable amounts - they must match the sum of line items in each VAT category. Source system must provide.

Code Example

<cac:InvoiceLine>
  <cbc:ID>1</cbc:ID>
  <cac:InvoicePeriod>
    <cbc:StartDate>2024-12-01</cbc:StartDate>
    <cbc:EndDate>2024-12-31</cbc:EndDate>
  </cac:InvoicePeriod>
  <!-- line content -->
</cac:InvoiceLine>

Common Causes

·VAT breakdown missing taxable amount (TaxableAmount)
·Tax subtotal created without tax base value
·TaxSubtotal/TaxableAmount not mapped in export
·VAT calculation skipped taxable amount field
·Tax category present but base amount missing

Seeing this in production? The API handles BR-45 automatically. See the fix response →

Commonly Seen In

All invoicing software

Frequently Asked Questions

Service lines should specify the billing period.

Add the required `cac:TaxSubtotal` element to your Invoice. Ensure it contains a valid value per EN 16931. This error involves a protected field — Invoice Navigator flags it in your pipeline so your team can correct it at the source.

BR-45 is a warning that may not always cause rejection, but it indicates a potential compliance issue that should be addressed to ensure full compatibility.

BR-45 involves a financial or legal field that cannot be auto-modified by policy. Invoice Navigator detects and flags this error immediately, but the correction must be made manually in your ERP or invoicing software.

BR-45 is commonly seen in exports from All invoicing software. These software packages sometimes generate invoices that need adjustment to meet full compliance standards.

Detect BR-45 Before Submission

This error involves a financial or legal field that cannot be auto-modified. The compliance engine flags it immediately with a clear diagnosis so your team can fix it at the source.

Get API Access View API Documentation

BR-45:Each VAT breakdown (BG-23) shall have a VAT category taxable amount (BT-116).