Schedule K-1 (Form 1065) - Gross Nonfarm Income
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Generally, the amount reported on Schedule K-1 (1065), Box 14, Code C Gross Nonfarm Income is not used on the individual income tax return. This amount would only be used if you are using the nonfarm option method for calculating your self-employment tax on Schedule SE.

Per the Partner's Instructions for Schedule K-1 (Form 1065), page 13:

Code C. Gross nonfarm income. If you are an individual partner, use this amount to figure net earnings from self-employment under the nonfarm optional method on Schedule SE (Form 1040 or 1040-SR), Section B, Part II.

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