`BR-DE-21`

XRechnung (KoSIT) · validation rule

XRechnung (KoSIT)Warning

The specification identifier (BT-24) is not the XRechnung URN. For XRechnung 3.0 the sender must set cbc:CustomizationID / ram:GuidelineSpecifiedDocumentContextParameter/ram:ID to 'urn:cen.eu:en16931:2017#compliant#urn:xeinkauf.de:kosit:xrechnung_3.0' (or the extension/CVD variant '…#conformant#urn:xeinkauf.de:kosit:extension:xrechnung_3.0').

Field: document.specification_id (BT-24)
Rule set: XRechnung (KoSIT)
Rule-set version: XRechnung 3.0.2 Schematron 2.6.0 · in force since 2026-10-17 · Rule-set changelog
Who has to fix it: The sender

This is a property of the file you received, so it cannot be corrected on your side without changing the document — ask the supplier to reissue it.

Worked example · UBL

The specification identifier (BT-24) must name the current XRechnung: the 3.0 urn under xeinkauf.de, not the retired xoev-de 2.x identifier.

Fails this rule

<cbc:CustomizationID>urn:cen.eu:en16931:2017#compliant#urn:xoev-de:kosit:standard:xrechnung_2.3</cbc:CustomizationID>

Passes

<cbc:CustomizationID>urn:cen.eu:en16931:2017#compliant#urn:xeinkauf.de:kosit:xrechnung_3.0</cbc:CustomizationID>

Worked example · CII

Fails this rule

<ram:ID>urn:cen.eu:en16931:2017#compliant#urn:xoev-de:kosit:standard:xrechnung_2.3</ram:ID>

Passes

<ram:ID>urn:cen.eu:en16931:2017#compliant#urn:xeinkauf.de:kosit:xrechnung_3.0</ram:ID>

Check your own invoice

Drop the file that failed. We parse it, run the official rule sets against it and list every finding with a fix — 20 invoices per day, no key, nothing stored.

Open the live demo

Same explanation over the API: GET /v1/rules/BR-DE-21?lang=en