Without a tax number, almost nothing works in self-employment: you cannot issue invoices and you cannot report any turnover to the tax office. Every person who becomes self-employed – whether as a freelancer, a trader or the founder of a corporation – needs one from day one. How it works, you can read here: from the tax registration questionnaire to your first invoice.
The key points at a glance:
- You apply for the Steuernummer at your tax office (Finanzamt) via the “tax registration questionnaire”, most easily online through ELSTER, within one month of starting out.
- It is mandatory for all self-employed people: freelancers, traders and small business owners (Kleinunternehmer) alike.
- Do not confuse it with the tax ID (Steuer-ID): you get that one automatically, the tax number only on request.
- Processing usually takes two to four weeks. After that, the number belongs on every invoice you write.
What is a Steuernummer?
Definition and legal basis
The Steuernummer is the number under which your local tax office (Finanzamt) records you as a taxpayer. You are assigned one as soon as you become self-employed and register your business activity with the tax office – the obligation follows from the Fiscal Code (Abgabenordnung), more precisely from the section on tax registration. Every taxable person receives their own number that identifies them uniquely.
In everyday life, you come across the tax number mainly in two places. First, on your invoices – there it is one of the mandatory details. Second, in correspondence with the tax office. Every income tax return, every advance VAT return and every letter runs through this number. Without it, the tax office cannot clearly assign you within its system.
Difference from the tax identification number
The Steuer-ID and the Steuernummer sound similar, but they mean two very different things. The Steuer-ID – officially the tax identification number – you get automatically: either right at birth if you are born in Germany, or shortly after moving there, as soon as you register for the first time. Eleven digits, assigned once, for life. A change of address does not affect it, and neither does a new trade. It is needed everywhere your income tax is involved – employer, bank, tax office all fall back on the same number so that documents can be assigned to you clearly. Mislaid the letter? No drama: you can request your tax ID online from the Federal Central Tax Office (BZSt), and it will be sent to you again by post.
The Steuernummer is a different story. You do not get it automatically, but only once you become self-employed and submit the tax registration questionnaire. Unlike the tax ID, it is tied to your local tax office – and if something changes in your business situation, for example a move into the area of a different tax office, the number changes too.
Who needs a tax number?
Self-employed people and freelancers
Whether you work as a copywriter, consultant, designer or in another liberal profession – as soon as you get going, you as a freelancer have to apply for a tax number. And that is regardless of how much comes in at the end. Even someone who only freelances on the side and takes in a few hundred euros a month cannot get around the registration – the tax office makes no exception here. If you are starting out solo, our business account for freelancers keeps things tidy from day one.
The tax number is applied for via the tax registration questionnaire, within one month of taking up the activity. After that, your personal tax number lands in your letterbox, and from that moment it belongs on every invoice you write. Important: your old tax ID does not count here, nor does a tax number from a previous employment. For your freelance activity you need your very own, separate number.
Traders (Gewerbetreibende)
Anyone who runs a trade cannot avoid a tax number. As soon as you register your trade with the trade office (Gewerbeamt), your local tax office is informed automatically. That does not mean you can sit back, though: you still have to submit the tax registration questionnaire yourself and actively via ELSTER, within one month of taking up your activity. Only then does the tax office assign your tax number. When exactly the obligation kicks in is covered in our guide on when you have to register a business.
So if you want to apply for a tax number for a trade, there is no way around these two steps: first the registration with the trade office, then the tax registration with the tax office. Without this number you can neither issue legally sound invoices nor pay your VAT correctly.
Small business owners under § 19 UStG
Small business owners (Kleinunternehmer) often believe they do not need a tax number – after all, they do not show any VAT. But that is not true. Even under the small business rule you register with the tax office and get your own tax number.
The number has nothing to do with VAT. It assigns your income for income tax purposes. And it belongs on every invoice, together with the reference to § 19 UStG. If it is missing, the invoice counts as incomplete, and your customers run into trouble when booking it. What lies behind the status is explained in our guide on becoming a Kleinunternehmer.
You apply for the tax number for your small trade just like any other self-employed person: via the tax registration questionnaire at the responsible tax office.
Applying for a tax number online: step-by-step guide
You can apply for the tax number online entirely through ELSTER – with no paperwork or trip to an office. The following four steps show you exactly what to prepare, how to fill in the questionnaire and how long it takes until the number is ready.
Applying for a tax number in 4 steps
The first step depends on what you do. If you run a trade – for example retail, a craft or an agency – you register with your local trade office, which these days can often be done online through your city’s service portal. Once you have your trade licence, the trade office automatically informs your local tax office. If, on the other hand, you work as a freelancer – for example as a consultant, designer or in another liberal profession under § 18 EStG – the trip to the trade office is skipped entirely. You register directly with the tax office, and actively: an informal letter or the tax registration questionnaire via ELSTER is enough. The same deadline applies either way: you have one month from taking up your activity.
The tax registration questionnaire is the central form for your registration. You fill it in electronically via ELSTER – the tax office only accepts a paper form in exceptional cases. You will find the form to apply for a tax number there under “Forms & services” → “All forms”. Important: since 2021 you have to submit it yourself and actively; it is no longer sent to you automatically.
Applying for a tax number online means, in practice: fill in the questionnaire and send it off through your ELSTER account. First you create your ELSTER account, if you do not have one yet – registration takes a few days, because parts of the login details are sent to you by post, so plan for that in good time. Then you log in with your certificate and transmit the completed questionnaire electronically. After sending it, you get a confirmation of receipt and can follow the processing status in your ELSTER account. The advantage over the classic postal route: you save on postage, see immediately whether the transmission worked, and do not have to wait for a letter to arrive at the tax office.
After two to four weeks you get post from the tax office: a letter with your new tax number. Sometimes it also appears in your ELSTER mailbox, if you opted for electronic notification – but the standard route remains the classic letter. Keep the letter safe. You need the number on every invoice from now on, and you should note it down separately – for example in your accounting software – in case the letter is ever mislaid. Once you have it, you can officially get started: issue invoices, sign contracts, everything now runs through this number.
Filling in the tax registration questionnaire
With the questionnaire, every detail counts. Above all the VAT-related entries. A mistake here often drags on through your accounting for years. The next sections show you what matters.
VAT-related entries
Two questions in the questionnaire decide on your VAT: how much turnover you expect in the first and in the second year, and whether you want to use the small business rule.
Estimate your turnover realistically, neither too low nor too high. Set it too low and you pay up later in one lump sum. Set it too high and you pay unnecessarily high VAT in advance. Both can be avoided if you calculate honestly.
For the small business rule, this applies: if you deliberately decide against it, even though you would stay within the threshold, that binds you for five years. Switching back is not possible during that time. So think the choice through carefully before you tick the box.
Small business rule: a decision aid
The small business rule under § 19 UStG is worth it above all at the start of your self-employment. If your turnover in the previous year was below €25,000 and you expect at most €100,000 in the current year, you can waive showing VAT – then you write invoices without VAT, save yourself the advance VAT return and have less accounting effort overall.
The catch: you also get no input VAT refunded. So if you buy expensive tech or equipment, you simply pay the VAT on it without being able to reclaim it. On top of that, some customers, especially larger firms, read the reference to § 19 UStG as a sign of a very small business.
Whether the rule is worth it for you depends above all on how you work. If larger purchases are coming up or you mainly work with corporate clients who are themselves entitled to deduct input VAT, you are often better off waiving the rule. If you are just starting out, have few expenses and work mainly with private customers, the small business rule usually speaks for itself.
For applying for the tax number for your small trade, this decision changes nothing, by the way – you get the number in any case, regardless of which option you tick in the questionnaire.
The tax number and invoicing
No tax number, no valid invoice. The VAT Act prescribes exactly what belongs on every invoice – here are the most important points.
Mandatory details on invoices
Under § 14 (4) UStG, every invoice must contain these details:
If one of these details is missing, the invoice counts as incomplete. For your customer, that means, in the worst case: no input VAT deduction.
What happens after you receive the tax number?
Your tax number has arrived – congratulations. But that is also where the actual work begins: ongoing obligations towards the tax office. What is coming your way now and where else you need the number, the next sections show you.
Overview of tax obligations
With the tax number come ongoing obligations. The most important at a glance:
For a deeper overview of all the levies, see our guide to taxes for the self-employed.
Use in business dealings
Your tax number accompanies you above all in contact with the tax office. It appears on every letter, every tax return and every advance return you submit. It also crops up occasionally in contracts with business partners, for example when a client needs it for their own bookkeeping. It does not, however, belong in the legal notice (Impressum) of your website – there, only the VAT ID is mandatory, if you have one. The ordinary tax number has no place there, and many people put it in by mistake anyway, which creates unnecessary risks.
Digital tools and support for founders
Tax number sorted – now it is on to the day-to-day: writing invoices, organising receipts, keeping the overview. Digital tools take a fair bit off your plate, from expense management to the link with your accounting.
Vivid Money business solutions
For the daily work afterwards, the Vivid business account is a good fit. You separate business and private bookings cleanly from the start, can capture receipts directly in the app and keep an eye on your expenses in real time. You can open accounts in more than 20 currencies directly in the app, which is especially handy if you work with international clients.
For the tax return, the account can be linked directly with tools such as DATEV, sevDesk or lexoffice – your transactions and statements sync automatically, without you having to transfer any data by hand. Everything is managed through the app, which works just as well on the go as at your desk.
A business account for your self-employment
Separate private and business finances from the start. With the Vivid business account you capture receipts in the app, hold accounts in more than 20 currencies and link your account directly with DATEV, sevDesk or lexoffice.
Conclusion: applying for a tax number – your start into compliant self-employment
Nothing works in self-employment without a tax number, but applying for it is straightforward in itself: submit the tax registration questionnaire via ELSTER, then wait. The more carefully you fill in the questionnaire, the more smoothly the tax office can process it.
With the Vivid business account you have a reliable partner for your finances at your side from the start. Separate business and private expenses cleanly, keep the overview in real time and link your account directly with your accounting.
Frequently asked questions (FAQ)
Where can you apply for the tax number?
At the responsible tax office (Finanzamt), via the tax registration questionnaire. It is submitted electronically through ELSTER.
Do small business owners need a tax number?
Yes. The small business rule only concerns VAT, not the tax number itself. You still need it – for income tax and on every invoice.
Can I have more than one tax number?
Yes, that happens. If you carry out several self-employed activities or want to apply for a tax number for your company while you already have one privately, the tax office assigns a separate number for it. A move into the area of a different tax office can also result in a new tax number.
Note: the contents of this blog serve general information purposes only and do not constitute legal, financial, investment or tax advice. They are not a recommendation or a basis for financial decisions. All information relates to the status of July 2026 and may change. Before you act on the basis of this information, please seek advice from qualified professionals who take your personal situation into account.
