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Begin by adding the appropriate schedule to the tax return (SCH C, E, or F).
Navigate to the 1099-K. Select the Link to (1040, SCH C, E, or F) box in box 1a of Form 1099-K.
Select Choices from the Active Options Window.
Select the SCH you wish to link to. Double-click to link.
You can view the linked income on SCH C Line 1.