If you have a sole proprietorship or a single-member LLC, you likely can file a Schedule C (Form 1040) Profit or Loss From Business on your personal Form 1040 U.S. Individual Income Tax Return tax return. For a formal partnership, you should file Form 1065 U.S. Return of Partnership Income. For an S-Corporation, you should file Form 1120-S U.S. Income Tax Return for an S Corporation. For a C-Corporation, you should file Form 1120 U.S. Corporation Income Tax Return.
See IRS Publication 3402 Taxation of Limited Liability Companies for more information on which form to use for your LLC.
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