Some weeks (2-4) after you apply for a health insurance you should receive your social security number by mail. This number is called the Sozialversicherungsnummer, Versicherungsnummer, Rentenversicherungsnummer or RNVR.
If you need to have your social security number sooner than that (e.g your employer is requesting it), you can send an email (or call) your health insurance provider (e.g: TK) and ask for this number.
The Tax Id (also known as Steueridentifikationsnummer, Identifikationsnummer or Steuer-ID) is an 11 digit number issued by the German Federal Tax Office that identifies you. This number is unique and will never change. If you want to work in Germany, you need to provide this number to your employer, otherwise tax will be deducted from your income at the maximum rate (source).
There are two ways of obtaining your Tax Id:
- Simply wait until you receive it by email. This number will be automatically generated and sent to you between 2 to 4 weeks after you've done your address registration.
- If you can't wait 2 to 4 weeks to get your Tax Id, you can go directly to the Finanzamt of your district (tip: use google to find the address) and ask for it. Take your passport with you. Differently from the Bürgeramt, usually there are no lines in the Finanzamt and you do not need to go early. Please note that you should wait at least one week after your address registration before you go to the Finanzamt, as this number takes some days to be generated.
If you have already completed the above steps before, but then lost the number, you can request it online: https://www.bzst.de/DE/Steuern_National/Steuerliche_Identifikationsnummer/ID_Eingabeformular/ID_Node.html.
- Do not confuse the Steueridentifikationsnummer (Tax Id) with the Steuernummer. The latter is something totally different used by freelancers. This guide explains the difference.
- If you decide to go to the Finanzamt, take this opportunity to find out your tax category. If you are married (and your spouse/civil partner) does not have an income, it might be a good idea to change the tax category for both of you, as this might increase your net income per month. Please refer to the website http://www.parmentier.de/steuer/steuer.htm?wagetax.htm to understand how your tax category affect your monthly income. You can click here to find out how to change your tax class.