A sole proprietor pays taxes by reporting income (or loss) on a T1 income tax and benefit return.  You will need to file a T1 so that you can pay income tax for the year, want to make CPP and EI contributions and if you disposed of a capital property.
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All resident corporations (except tax-exempt corporations need to file a corporation income tax (T2) return every tax year even if there is no tax payable. This includes:
non-profit organizations
tax-exempt corporations
inactive corporations
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