How to file your income tax return in the United States
Filing your income tax return in the United States: who must file, the tax year and deadline, what documents you need, and what happens if you are late.
Most people with income above the standard deduction file Form 1040; self-employed people file Schedule C and pay self-employment tax once net earnings exceed $400.
Tax year and deadline
Tax year is the calendar year; returns are due 15 April, extendable to 15 October (payment is still due in April). Estimated tax is paid quarterly.
Filing step by step
Gather W-2s, 1099s, and business income and expense records.
File electronically with IRS Free File or tax software, or with a preparer.
Self-employed: complete Schedule C and Schedule SE.
Pay by 15 April or set up an IRS payment plan.
Penalties for filing or paying late
Late-filing and late-payment penalties on a federal return are set by 26 U.S.C. § 6651. For failure to file, the addition is 5% of the tax required to be shown for each month or part of a month the return is late, up to 25%. For failure to pay, the addition is 0.5% of the unpaid tax per month or part of a month, up to 25%. When both apply in the same month, the filing addition is reduced by the payment addition. A return more than 60 days late carries a minimum filing addition of the lesser of $435 or 100% of the tax required to be shown, with the dollar figure adjusted for inflation. The payment rate becomes 1% a month after the IRS gives notice of intent to levy or demands immediate payment.
Written from published tax-authority guidance and reviewed on 2026-10-11. Everything here is indicative rather than a ruling on your circumstances, and rules change. Confirm anything you rely on with Internal Revenue Service (IRS) and state departments of revenue before acting on it, and tell us if you find something out of date so we can correct it.
This guide explains the rules in general terms and is not tax advice for your circumstances. Confirm your position with a qualified adviser or with Internal Revenue Service (IRS) and state departments of revenue.