Fix BR-CO-20: Invoice line period date (BT-134/BT-135) missing

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What does BR-CO-20 mean?

If a period is used for an invoice line, the start or the end date must be set. That way the period is defined.

Common causes of BR-CO-20

The invoice line period was created, but neither start nor end date was set.
The line's delivery date was written into the wrong element.
An empty 'ram:BillingSpecifiedPeriod' was left on line level.

How to fix BR-CO-20

Find the faulty spot in the XML. Open the XML of the invoice and go to field BG-26 along this XPath://ram:SpecifiedLineTradeSettlement/ram:BillingSpecifiedPeriod
Apply the fix. If an invoice line period (BG-26, 'ram:BillingSpecifiedPeriod' inside the line) is used, at least the start date (BT-134, 'ram:StartDateTime') or the end date (BT-135, 'ram:EndDateTime') must be filled. Add one of the two dates in the line period group or remove the empty group.
Validate again. Save the file and validate it again to check that BR-CO-20 is no longer reported.

Concrete fix

If an invoice line period (BG-26, 'ram:BillingSpecifiedPeriod' inside the line) is used, at least the start date (BT-134, 'ram:StartDateTime') or the end date (BT-135, 'ram:EndDateTime') must be filled. Add one of the two dates in the line period group or remove the empty group.

XPath//ram:SpecifiedLineTradeSettlement/ram:BillingSpecifiedPeriod

Before / after: the XML example

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

Wrong

<ram:SpecifiedLineTradeSettlement>
  <ram:BillingSpecifiedPeriod>
  </ram:BillingSpecifiedPeriod>
</ram:SpecifiedLineTradeSettlement>

Correct

<ram:SpecifiedLineTradeSettlement>
  <ram:BillingSpecifiedPeriod>
    <ram:StartDateTime>
      <udt:DateTimeString format="102">20260401</udt:DateTimeString>
    </ram:StartDateTime>
  </ram:BillingSpecifiedPeriod>
</ram:SpecifiedLineTradeSettlement>

Frequent questions about BR-CO-20

How does BR-CO-20 differ from BR-CO-19?

BR-CO-19 concerns the invoicing period on document level (BG-14), BR-CO-20 the period of a single invoice line (BG-26). The rule is the same: at least a start or an end date.

Where does the invoice line period sit in CII?

In 'ram:BillingSpecifiedPeriod' inside 'ram:SpecifiedLineTradeSettlement' of the respective line, with 'ram:StartDateTime' (BT-134) and 'ram:EndDateTime' (BT-135).

Related error codes

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