You must register your business with the city or municipal administration (town hall) in which the business or business premises are opened (§ 138 AO - Notification of gainful employment).
You can also obtain the necessary registration forms there. Many municipalities already offer electronic procedures for this.
In addition, your local tax office must be notified of the opening of the business establishment within one month (Section 138 Paragraph 1b in conjunction with Paragraph 4 AO). To do this, please complete the electronic questionnaire for tax registration for sole proprietorships. The electronic input help will assist you in completing the questionnaire. The prerequisite is the one-time creation of a ELSTER user account. Alternatively, you can create a ELSTER-Light account. This allows you to simply register for the notification of the commencement of a commercial activity and later have the option of converting the certificate into a regular certificate. You can then use all the advantages of ELSTER. The tax office will then assign you a tax number. Please use this tax number to submit your tax returns, advance VAT returns and, if applicable, income tax returns.
If the activity you wish to carry out is not a commercial activity but a freelance activity, e.g. as an architect, and you do not need to register a business with your municipal or local authority, you must notify your tax office of the commencement of a freelance activity using the electronic questionnaire for tax registration for sole proprietorships.
If you set up a partnership/joint venture, joint venture or corporation, you must complete the questionnaire for tax registration: Formation of a corporation or cooperative, corporation under foreign law, formation of a partnership/joint venture or participation in a partnership/joint venture.