For tax registration, please submit the following fully completed and signed documents:
(vgl. Formular-Management-System der Bundesfinanzverwaltung (formulare-bfinv.de):
Unternehmen / Umsatzsteuer / Fragebogen zur umsatzsteuerlichen Erfassung von im Ausland ansässigen Unternehmern)

1. VAT registration form for non-resident businesses
    
2. Residence certificate from the Turkish revenue administration (https://www.gib.gov.tr/en)
    
3. Supplements to the VAT registration form for non-resident businesses
   Supplement 1 - Corporations and partnerships
   Continuation sheet for the supplementary sheet 1 “Corporations
   Supplement 2 - Facilities
   Supplement 3 - Passenger transport services
    
4. Authorisation for e-mail communication with the Local Tax Office Dortmund-Unna
    
5. Guidance notes for completing the VAT registration form

For tax registration, please submit the following fully completed and signed documents:
(vgl. Formular-Management-System der Bundesfinanzverwaltung (formulare-bfinv.de):
Unternehmen / Umsatzsteuer / Fragebogen zur umsatzsteuerlichen Erfassung von im Ausland ansässigen Unternehmern)

1. VAT registration form for non-resident businesses
    
2. Residence certificate from the Turkish revenue Administration (https://www.gib.gov.tr/en)
    
3. Supplement to the VAT registration form for non-resident businesses
   Supplement - Online trade in goods
    
4. Authorisation for e-mail communication with the Local Tax Office Dortmund-Unna
    
5. Guidance notes for completing the VAT registration form

The entrepreneur has to report his sales and, if applicable, input tax amounts to the tax office monthly or quarterly by the 10th of the following month (advance sales tax return). The entrepreneur must calculate the payment charge or refund himself and transfer it to the tax office without further request. In addition, an annual VAT return has to be submitted once a year.
 
These tax returns has to be submitted electronically. Details of the electronic data transmission procedure can be found at www.elster.de  or www.finanzamt.de as well as with your Local Tax Office, your tax advisor or your data processing company.
 
Tax-relevant documents have to be stored and sent to the tax office upon request.
 

As a Turkish entrepreneur, you carry out sales in Germany and are obliged to submit advance VAT returns. Advance VAT returns are submitted either monthly or quarterly.
 
The submission of an advance return is also required if you have not made any sales in Germany during the period covered by the advance return and no input tax has been incurred on purchases of goods or costs in Germany.
If so, enter the number 0 under Sales and Input Taxes. Otherwise, you will receive a reminder to submit the advance return.

Your Turkish company has incurred costs with German VAT when operating in Germany. However, your company did not carry out any sales in Germany or only carried out sales for which the service recipient owes the tax.
 
The Federal Central Tax Office (BZSt) is responsible for processing a so-called application for input tax refund.
 
You can find further information on the refund of German VAT on the homepage of the Federal Central Tax Office.