errorEN 16931

`BR-28`:The Item gross price (BT-148) shall NOT be negative.

The Item gross price (BT-148) shall NOT be negative.. Review the `cbc:BaseQuantity` element.

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: Buyer company name

What is BR-28?

BR-28 is a fatal validation rule defined in the EN 16931 specification. It validates the RegistrationName element under PartyName > Name or cac:PartyLegalEntity 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:AccountingCustomerParty/cac:Party/cac:PartyName/cbc:Name or cac:PartyLegalEntity/cbc:RegistrationName

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Why This Error Matters

Invoice rejected. Negative gross prices are mathematically invalid.

BR-28 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-28
·Specification: EN 16931

How to Fix It

Add trading name

In PartyName/Name

Or legal name

In PartyLegalEntity/RegistrationName

Match records

Should match buyer master data

Before / After

Failing XML

<cac:Price>
  <cbc:BaseQuantity>-100.00</cbc:BaseQuantity>
</cac:Price>

Corrected XML

<cac:Price>
  <cbc:BaseQuantity>100.00</cbc:BaseQuantity>
</cac:Price>

Technical Reference

XPath

XPath: /Invoice/cac:AccountingCustomerParty/cac:Party/cac:PartyName/cbc:Name or cac:PartyLegalEntity/cbc:RegistrationName

SpecEN 16931

StrategyRequires user to provide buyer trading name or legal registration name

Code Example

<cac:AccountingCustomerParty>
  <cac:Party>
    <cac:PartyName>
      <cbc:Name>Customer Corp</cbc:Name>
    </cac:PartyName>
  </cac:Party>
</cac:AccountingCustomerParty>

Common Causes

·Negative gross price entered in source system
·Calculation error when applying surcharges
·Base amount for allowance set incorrectly
·Data corruption during system migration
·Manual price override with wrong sign

Seeing this in production? The API handles BR-28 automatically. See the fix response →

Commonly Seen In

All invoicing software

Frequently Asked Questions

The buyer must have either a trading name or legal registration name.

This requires user input to resolve. Provide the correct value for `cbc:BaseQuantity` (BT-148). Invoice Navigator detects this error and prompts for the required business data before applying a safe fix.

Yes, BR-28 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.

BR-28 requires specific business data to resolve. Invoice Navigator detects the error and guides you through providing the needed information, then applies the fix with full audit documentation.

BR-28 is commonly seen in exports from All invoicing software. These software packages sometimes generate invoices that need adjustment to meet full compliance standards.

Resolve BR-28 with Guided Input

The compliance engine detects this error and prompts for the required business data before applying a safe, auditable fix.

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BR-28:The Item gross price (BT-148) shall NOT be negative.