Credits and deductions

TurboTax makes it's calculation based on the numbers that have been entered, the software doesn't know anything about tax treaties. The 20(11) or 20(12) deductions are based on tax treaty information, which is why TurboTax Online asks "Please verify that you are entitled to claim a 20(11) or 20(12) deduction." . You have to make sure the numbers entered for the 20(11) or 20(12) deductions are correct based on the country of origin of the income/tax paid because TurboTax Online doesn't know. If you're not sure, then it's best to get that information from the CRA or from someone knowledgeable in the treaties you are dealing with before you file, instead of waiting for an audit.