Yes, you can file your 2015 and 2016 tax returns online. Please visit File past year’s taxes to download the software for the 2015 and 2016 tax years.
Once you finish filling your tax returns, please note that if you are reporting a tax return related to years 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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