errorEN 16931

BR-AG-01:IPSI VAT breakdown required when IPSI used on lines

When using the IPSI VAT category (M) on invoice lines, allowances, or charges, you must have exactly one matching VAT breakdown section for IPSI.

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-AG-01?

BR-AG-01 is a fatal validation rule defined in the EN 16931 specification. It validates the ID="M"]. IPSI (category M) is the Ceuta and Melilla indirect tax. When lines or document-level items use this category, the VAT breakdown must include a corresponding TaxSubtotal. element under TaxTotal > TaxSubtotal[cac:TaxCategory 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:TaxTotal/cac:TaxSubtotal[cac:TaxCategory/cbc:ID="M"]. IPSI (category M) is the Ceuta and Melilla indirect tax. When lines or document-level items use this category, the VAT breakdown must include a corresponding TaxSubtotal.

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

Why This Error Matters

Invoice will be rejected. IPSI (Ceuta/Melilla indirect tax) transactions must follow specific rules for Spanish territory tax compliance.

BR-AG-01 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-AG-01
  • ·Specification: EN 16931

How to Fix It

1.

Find IPSI lines/allowances/charges

2.

Check for IPSI VAT breakdown

3.

Create IPSI breakdown if missing

4.

Ensure only one IPSI breakdown

5.

Validate the result

Before / After

Failing XML
<Invoice>
  <cac:InvoiceLine>999.99</cac:InvoiceLine>
  <!-- Does not match expected calculation -->
</Invoice>
Corrected XML
<Invoice>
  <cac:InvoiceLine>100.00</cac:InvoiceLine>
  <!-- Matches expected calculation -->
</Invoice>

Technical Reference

XPathXPath: /Invoice/cac:TaxTotal/cac:TaxSubtotal[cac:TaxCategory/cbc:ID="M"]. IPSI (category M) is the Ceuta and Melilla indirect tax. When lines or document-level items use this category, the VAT breakdown must include a corresponding TaxSubtotal.
SpecEN 16931
Strategy1. Find all lines/allowances/charges with this VAT category. 2. Ensure exactly one TaxSubtotal with matching category exists. 3. Create if missing.

Common Causes

  • ·IPSI tax category used on lines but missing from VAT breakdown
  • ·Tax breakdown not generated for Ceuta/Melilla IPSI transactions
  • ·VAT summary calculation skipped IPSI category
  • ·Export template missing IPSI breakdown section
  • ·Tax engine not configured for IPSI category code L

Seeing this in production? The API handles BR-AG-01 automatically. See the fix response →

See Also

Related Errors

Last updated: 27 February 2026

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Handle BR-AG-01 Automatically in Your Pipeline

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