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- When submitting before the 1st of December 2019, the BZSt Number has to be added instead of the Steuernummer.
- When submitting on or after the 1st of December 2019, the Steuernummer has to be provided, but in a special format:
- No special characters like "/" are allowed.
- The Steuernummer has to be provided as a 12-diget, so called "Bundesschema" (see more information and sample Steuernummern on Wikipedia).
- If the Steuernummer is only 9 or 10 digest, the Bundesland Finanzamtsnummer has to be added as a prefix.
- If the Finanzamtsnummer is not know, it can be found out by searching the city of the Finanzamt in the Gemfa 2.0 tool on the BZSt Webpage:
https://www.bzst.de/DE/Service/Behoerdenwegweiser/Finanzamtsuche/GemFa/finanzamtsuche_node.html
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