Does the app apply the double taxation agreement (DTA)? Gizem K. April 22, 2024 09:53 Updated No. Cases in which double taxation (DTA) would occur are not yet supported by our app. Related articles Can I use Taxfix as an expat or relocator? In which currency do I declare non-German income in Taxfix? How is non-German income taxed in Germany? Why do I have to declare my foreign income in my German tax declaration? Do I have to file a tax return as an expat or relocator?