If you've entered an amount from any of the boxes on the slips listed here, you have what the Canada Revenue Agency (CRA) considers to be self-employment or business income:

T4 slip: box 81, 82 or 83
T4A slip: box 20 or 48
T4A slip: box 28 and you selected Yes to the question Does the income declared in Box 028 consist of fees collected for services you provided? in TurboTax Online (needs to say NO to indicate no self-employment)
T3 slip: box 24 (foreign business income)

If you have an amount in any of these boxes, TurboTax will ask additional questions to report the income as self-employment/business income. You only need to answer basic information, such as business name and address (can be your own), industry code, and fiscal period (Jan 01 to December 31). 

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