Did you find out if this is a software problem, seems i'm having the same issue. My net federal is the same as the federal tax even I having non-refundable tax credits.

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I also had a problem with the calculation of the net federal tax.   The CRA reassessed me and showed my Fed tax owing was $222.27 more than what Turbo Tax calculated.    My total income, deductions and net income all matched, yet the calculation for federal tax was different.   Luckily I signed into my CRA account to check for mail, otherwise I could have been late with my remittance.

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