How do I fix BR-Z-04?

This requires user input to resolve. Provide the correct value for `cac:AllowanceCharge` (BG-21) (BR-Z-04). You can also use Invoice Navigator's compliance engine to correct this automatically in your pipeline.

Is BR-Z-04 a critical error?

Yes, BR-Z-04 is a critical error that will cause invoice rejection. It must be fixed before submission.

Can BR-Z-04 be automatically fixed?

Many instances of BR-Z-04 can be automatically corrected using Invoice Navigator's compliance engine. The fix is applied in your pipeline with full audit evidence.

errorEN 16931

`BR-Z-04`:When using this VAT category, the seller must have a VAT identifier, tax...

When using this VAT category, the seller must have a VAT identifier, tax registration, or tax representative (applies to `cac:AllowanceCharge`, rule BR-Z-04).

Severity

Fatal

Rule set

EN 16931

Country

All EU

Fix type

INPUT REQUIRED

Engine Classification

Business data required · Explicit input workflow · No assumptions made

Required input: Seller VAT Identifier (BT-31)

What is BR-Z-04?

BR-Z-04 is a fatal validation rule defined in the EN 16931 specification. It checks whether when using this vat category, the seller must have a vat identifier, tax....

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.

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Why This Error Matters

Invoice will be rejected. Zero rated VAT (category Z) requires seller VAT registration, 0% rate, and correct breakdown. Zero rate is different from exemption - it still requires tax compliance.

BR-Z-04 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-Z-04
·Specification: EN 16931

Before / After

Failing XML

<Invoice>
  <cac:AllowanceCharge>INVALID_CODE</cac:AllowanceCharge>
</Invoice>

Corrected XML

<Invoice>
  <cac:AllowanceCharge>VALID_CODE</cac:AllowanceCharge>
</Invoice>

Technical Reference

SpecEN 16931

Strategy1. Check for existing VAT/tax identifiers. 2. If none, prompt for seller VAT number. 3. Add PartyTaxScheme.

Common Causes

·Zero rated charge missing seller VAT identifier
·Document charge with BT-102=Z needs seller tax ID
·Z category charge requires BT-31, BT-32, or BT-63
·Seller VAT registration absent for zero rate charge
·Zero rate on charges requires VAT registered seller

Seeing this in production? The API handles BR-Z-04 automatically. See the fix response →

Related Errors

BR-37

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

BR-AE-07

Document level charge with reverse charge must have 0% VAT rate

BR-AF-01

When an invoice contains items, allowances, or charges with VAT category...

Last updated: 27 February 2026

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

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BR-Z-04:When using this VAT category, the seller must have a VAT identifier, tax...