The tax number (Steuernummer) is assigned to you by the tax office, as soon as you start an employment.
The tax identification number is unique and remains the same throughout your life and cannot change. You need the tax number to file your tax return with the tax office, you can find it on your pay slip.
Unlike the tax identification number (SteuerID), the tax number can change if, for example, you get married, change your place of residence or start a new job. So it can also happen that you have several tax numbers.
In order to work with Zenjob, you need a tax identification number (SteuerID). You can find out where to get it here: What is a Tax ID and where do I get it?
If you have any further questions on this topic, click Submit a Request.