Fix BR-55: Preceding invoice reference without invoice number

BR-55 in your own invoice? Upload the file and find every error in seconds.

What does BR-55 mean?

The rule checks every reference to a preceding invoice (BG-3). In CII this reference sits in the element ram:InvoiceReferencedDocument. The core of the reference is the number of the preceding invoice (BT-25, ram:IssuerAssignedID). Without this number the recipient does not know which earlier invoice the reference points to. This is typical for corrective or final invoices.

Common causes of BR-55

ram:IssuerAssignedID is missing, only the date of the preceding invoice (ram:FormattedIssueDateTime) is set.
The element ram:InvoiceReferencedDocument was created empty.
The number of the preceding invoice was named in free text only, not in the structured field.
With several references, one of them lacks the number.

How to fix BR-55

Find the faulty spot in the XML. Open the XML of the invoice and go to field BT-25 along this XPath://rsm:CrossIndustryInvoice/rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeSettlement/ram:InvoiceReferencedDocument/ram:IssuerAssignedID
Apply the fix. Enter the child ram:IssuerAssignedID in the element ram:InvoiceReferencedDocument with the number of the preceding invoice (e.g. "RE-2026-014").
Validate again. Save the file and validate it again to check that BR-55 is no longer reported.

Concrete fix

Enter the child ram:IssuerAssignedID in the element ram:InvoiceReferencedDocument with the number of the preceding invoice (e.g. "RE-2026-014").

XPath

//rsm:CrossIndustryInvoice/rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeSettlement/ram:InvoiceReferencedDocument/ram:IssuerAssignedID

Before / after: the XML example

This is the spot in question before and after the fix (Cross Industry Invoice, ZUGFeRD/Factur-X).

Wrong

<ram:ApplicableHeaderTradeSettlement>
  <ram:InvoiceReferencedDocument>
    <ram:FormattedIssueDateTime>
      <udt:DateTimeString format="102">20260301</udt:DateTimeString>
    </ram:FormattedIssueDateTime>
  </ram:InvoiceReferencedDocument>
</ram:ApplicableHeaderTradeSettlement>

Correct

<ram:ApplicableHeaderTradeSettlement>
  <ram:InvoiceReferencedDocument>
    <ram:IssuerAssignedID>RE-2026-014</ram:IssuerAssignedID>
    <ram:FormattedIssueDateTime>
      <udt:DateTimeString format="102">20260301</udt:DateTimeString>
    </ram:FormattedIssueDateTime>
  </ram:InvoiceReferencedDocument>
</ram:ApplicableHeaderTradeSettlement>

Frequent questions about BR-55

When do I need a reference to a preceding invoice?

For example with corrective invoices, credit notes or final invoices that relate to an earlier invoice. The reference is optional, but as soon as it is there it needs the number.

Is the date of the preceding invoice mandatory?

No. Only the number (BT-25) is mandatory in the reference. You may add the date (ram:FormattedIssueDateTime) as well, but it does not replace the number.

Can I name several preceding invoices?

Yes. Repeat ram:InvoiceReferencedDocument for each preceding invoice. Every repetition needs its own ram:IssuerAssignedID.

Related error codes

Check BR-55 automatically

Instead of digging through the XML by hand you can validate your ZUGFeRD or XRechnung file online – upload the PDF or the XML and you get every error with rule ID, affected field, fix and XPath, as a readable report or as JSON through the API.

Validate online now Back to the lexicon