Assuming you are using TurboTax Online, in the Capital Gains and Capital Gains Deduction profile, check the first box: "Sold stocks, bonds, real estate, other capital property, or sold qualified small business corporation shares and/or qualified farm property and you have a capital gain or loss to report"

After that screen you will enter a new disposition or edit the one you want to do for FX, the type of capital property is: "Bonds/Other Properties" as this is the official line item that Canada Revenue Agency asks for you to report.

For more information, check out: Canada Revenue Agency (CRA) - Foreign Currencies

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