Income from Professional Services Taxed under A DTA Agreement

Income will be taxed in the state where the person is resident and practicing his profession. However, if he has a fixed base in the other Contracting State, the income, attributable to the fixed base, will be taxed in the other contracting state. Some treaties also specify that a professional will be liable to tax if he stays in another country for more than a specified number of days, (183 days for most treaties but 90 for the US) and derives income in that country, even if he does not have a 'fixed base' there.