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# For Meldefluss, where can I find my 13-digit Tax ID?

For the **cash register report via ELSTER in Meldefluss**, you need your **13-digit tax number** that is assigned to your business. This number is used by the tax office to correctly assign your cash register report.

###### What is the correct tax number?
For the cash register report, the rule is:

||| 👉 You need your 13-digit company tax number. This number is issued by the tax office responsible for the location of your register (the so-called local tax office / Betriebsstätten-Finanzamt).

###### Where can I find the tax number?
You can find your tax number on:
* Your VAT assessment notice
* A VAT advance return
* A letter from the tax office

Make sure the number has **13 digits**, without slashes or spaces.

| 💡 Example: 1121081508151

###### What if I only have the old, state-specific tax number?
In many documents, the tax number still appears in the old format, e.g. `12345/12345` (with a slash).

No problem! You can easily convert it: ➡️ Here is the official [**tax number converter**](https://www.ueberbrueckungshilfe-unternehmen.de/DE/Infothek/Steuernummer-Umrechner/steuernummer-umrechner.html)

|| Just enter the old number, and the tool will immediately show you the valid 13-digit version.

###### Good to know**:**
* The VAT ID number (e.g. `DE123456789`) is **not** the same as the tax number – don’t confuse the two.
* If you have multiple business locations, each one may have its own tax number.
* For sole proprietorships, the tax number may sometimes be the same as your personal one. The key is that it must correspond to your **business activity**.