If I've entered gig income using a T4A, why do I enter it again under business income? Is that not doubling the income amount?

[TurboTaxBrenda1]

As per the CRA- If you receive a T4A with Box 20 or Box 48 amounts, you are indeed self-employed for tax purposes as both of these boxes are used exclusively to report self-employment income. Therefore you would simply enter your name as business name and your home address as the business address. 

Since you’re self-employed, you’ll complete the business form T2125 – Statement of Business Activities. The upside is you can also claim expenses to offset that income on that form. 

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