A single-member LLC is not considered a separate entity for federal tax purposes. An LLC with only one member is treated as an entity disregarded as separate from its owner for income tax purposes (but as a separate entity for purposes of employment tax and certain excise taxes). This taxpayer is by default required to file Schedule C (Form 1040) Profit or Loss From Business with their personal tax return to report business income and expenses.
See IRS Publication 3402 for more information.
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