Steuer-ID: your German tax number explained properly

What the Steuer-ID is

The Steuer-ID (official name: Steueridentifikationsnummer, abbreviated IdNr) is your personal German tax identifier. Eleven digits, valid for life, and it doesn't change if you move, change your name or get married.

It's the German equivalent of a tax number, with one important difference: the state assigns it automatically, you don't have to apply for it. After your Anmeldung, your municipality passes your data to the Federal Central Tax Office (BZSt), which generates the number and posts it to you.

When it arrives

After the Anmeldung the number is assigned automatically. The letter with your Steuer-ID normally arrives within 2–4 weeks. The number is unique and stays the same even if you move to another city.

What it's used for

• By your employer, to calculate deductions and your tax bracket correctly.
• By the tax office, to link your returns and payments to you.
• By banks and insurers, in some cases, for tax reporting.
• For ELSTER, the online tax portal: you need it to register and file your return.

Without a Steuer-ID your employer often applies tax class VI, the least favourable one: it's worth handing it in as soon as you have it.

What you need to request it (if it hasn't arrived)

Step by step

1. Do the Anmeldung first. Without municipal registration the tax office doesn't have your data and can't assign a number.
2. Wait for the letter. It arrives in your name at your registered address. Keep the letter or at least the number.
3. If it doesn't arrive, request it online. On the tax office's website you'll find the reissue form: fill in your details and send the request. The number doesn't change.
4. Register on ELSTER. Once you have the number, create the account for your tax return (this also requires a second identity confirmation).
5. Give it to your employer. That way you move straight to the correct tax bracket and avoid over-deductions.

Family members' numbers

Your children also have a Steuer-ID: it's assigned automatically at birth or after the Anmeldung. Among other things it's needed to claim child benefit. If you've lost a family member's number, you can request it from the tax office with the relevant form.

Common mistakes

• Waiting to do the Anmeldung. Without registration the clock doesn't start.
• Changing address without an Ummeldung. Official letters won't reach you.
• Confusing the Steuer-ID with the Steuernummer. They're two different things: the first is personal, the second is local and tied to your tax affairs.
• Not giving it to your employer. You risk tax class VI and far higher deductions than necessary.