I filed my personal taxes but I don't know how to file my business taxes.

Filing your business taxes depends upon the entity type of your business.  If your business is a partnership, S Corp, or multi-member LLC, then a separate tax return needs to be filed for the business.  TurboTax Business can create these type of entity tax returns.

But, if your business is a sole proprietor or single member LLC, then your business income and expense activity should be included on your personal tax return on either Schedule C, E, or F (depending upon the type of business.) If this is the case for your business and you have already filed your personal tax return, you will need to file an amended tax return (Form 1040X) to include your business income and expenses.  See more information below on how to file an amended tax return for 2018:

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