errorEN 16931

BR-O-04:Surcharge marked as not subject to VAT but seller has a VAT number

One of your document-level surcharges uses VAT category "O" (Not subject to VAT), but the seller has a VAT identification number. These contradict each other — if the surcharge is not subject to VAT, the seller should not have a VAT ID on this invoice.

Severity
Fatal
Rule set
EN 16931
Country
All EU
Fix type
AUTO-FIX
Confidence
70%

Engine Classification

Present user with choice: remove seller VAT identifier (if truly not subject to VAT) or change the charge tax category (if VAT applies)

Confidence: 70% · Applied automatically in pipeline

What is BR-O-04?

BR-O-04 is a fatal validation rule defined in the EN 16931 specification. It validates the CompanyID element under Party > PartyTaxScheme 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:AccountingSupplierParty/cac:Party/cac:PartyTaxScheme/cbc:CompanyID

Why This Error Matters

Invoice will be rejected. "Not subject to VAT" (category O) has strict rules: no VAT identifiers allowed, no other categories permitted, and exemption reason required. Non-compliance prevents validation.

BR-O-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.

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-O-04
  • ·Specification: EN 16931

How to Fix It

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Before / After

Failing XML
<Invoice>
  <cac:AllowanceCharge>-100.00</cac:AllowanceCharge>
</Invoice>
Corrected XML
<Invoice>
  <cac:AllowanceCharge>100.00</cac:AllowanceCharge>
</Invoice>

Technical Reference

XPath/Invoice/cac:AccountingSupplierParty/cac:Party/cac:PartyTaxScheme/cbc:CompanyID
SpecEN 16931
Operationremove
StrategyPresent user with choice: remove seller VAT identifier (if truly not subject to VAT) or change the charge tax category (if VAT applies)

Common Causes

  • ·Category O charge found but seller VAT identifier present
  • ·Document charge with O category conflicts with BT-31
  • ·Seller VAT registration incompatible with O category charge
  • ·"Not subject to VAT" charge must not have seller VAT ID
  • ·Template structure incorrect for out-of-scope charges

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

See Also

Related Errors

Last updated: 27 February 2026

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Handle BR-O-04 Automatically in Your Pipeline

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