Business Income or Loss:

If you operated a business or practiced your profession as a sole proprietor, enter the Business income or losses in the indicated space. Business income is income received for products or services sold. For example, fees paid to a professional person are considered business income. Rents paid to a person in the real estate business are business income. Payments received in the form of property or services must be included in income at their fair market value
As a sole proprietor, you file Form 1040 Schedule C, or Form 1040 Schedule C-EZ , with Form 1040, to report the profit or loss from your business. Also, you must file Form 1040 Schedule SE if you had net earnings (from Schedule C or C-EZ) in excess of certain limit.

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