Yes, you can file your 2015 tax return online. Please visit File past year’s taxes to download the software for the 2015 tax year.
Once you finish filling your tax return, please note that if you are reporting a tax return related to a year before the 2017 tax year, you will need to print and mail your returns to the CRA. NETFILE service only accepts tax returns for tax years 2017 through 2020.
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