errorAUTpeppol-bis-3

BR-AT-01:Austrian UID number required

Austrian invoices must include the UID-Nummer (VAT ID) in ATU + 8 digits format.

Severity
Fatal
Rule set
peppol-bis-3
Country
AUT
Fix type
INPUT REQUIRED

Engine Classification

Business data required · Explicit input workflow · No assumptions made

Required input: Austrian UID Number (UID-Nummer)

What is BR-AT-01?

BR-AT-01 is a fatal validation rule defined in the peppol-bis-3 specification (AUT national rules). 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: XPath: /Invoice/cac:AccountingSupplierParty/cac:Party/cac:PartyTaxScheme/cbc:CompanyID

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Why This Error Matters

Austrian UID is required for VAT deduction by Austrian buyers.

BR-AT-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
  • ·Rejected by PEPPOL Access Points
  • ·Error returned: BR-AT-01
  • ·Specification: peppol-bis-3

How to Fix It

1.

Get UID

Format: ATU + 8 digits

2.

Add to invoice

In PartyTaxScheme/CompanyID

3.

Validate

Check with Austrian VAT validation service

XML Example

Generic example based on the rule's target XPath. Your actual XML structure may differ.

Before
<!-- Missing or empty element triggers cbc:CompanyID error -->
<cbc:CompanyID></cbc:CompanyID>
After
<!-- Provide the required value -->
<cbc:CompanyID>VALID_VALUE</cbc:CompanyID>

Technical Reference

XPathXPath: /Invoice/cac:AccountingSupplierParty/cac:Party/cac:PartyTaxScheme/cbc:CompanyID
Specpeppol-bis-3

Code Example

<cac:PartyTaxScheme>
  <cbc:CompanyID>ATU12345678</cbc:CompanyID>
  <cac:TaxScheme>
    <cbc:ID>VAT</cbc:ID>
  </cac:TaxScheme>
</cac:PartyTaxScheme>

Common Causes

  • ·Missing ATU prefix
  • ·Wrong length
  • ·Invalid UID

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

Commonly Seen In

Austrian invoicing systems

Frequently Asked Questions

Austrian invoices must include the UID-Nummer (VAT ID) in ATU + 8 digits format.

Add Austrian UID number. You can also use Invoice Navigator's automatic Fixer tool to correct this instantly.

Yes, BR-AT-01 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.

Many instances of BR-AT-01 can be automatically corrected using Invoice Navigator's Fixer tool. Upload your invoice and the tool will identify and fix common issues, including austrian uid number required.

BR-AT-01 is commonly seen in exports from Austrian invoicing systems. These software packages sometimes generate invoices that need adjustment to meet full compliance standards.

Related Errors

BR-29

Invoice period end date before start date

Last updated: 18 January 2026

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