The general rule
You generally must file a federal return if your gross income is at least the standard deduction for your filing status, with higher amounts if you're 65 or older. For 2025, that's $15,750 for a single filer under 65. Some people must file at lower income levels:
- You had $400 or more of net self-employment earnings.
- You are married filing separately (the threshold is very low).
- Someone can claim you as a dependent and you have unearned income, like interest, above a smaller limit.
- You owe special taxes, such as on an early retirement withdrawal, or received advance premium tax credit payments for Marketplace health insurance.