Does anyone know about this? I'm adding an amount for a T4A but it doesn't show up on line 3C of Business Income on form T2125B1.

Did you fill out T2125? Use the T2125 form to report either business or professional income and expenses. This form combines the two previous forms, T2124, Statement of Business Activities, and T2032, Statement of Professional Activities.

You do need to fill out a self-employment section to generate that information on line 3C.

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