IRS Form 1040

Form 1040: U.S. Individual Income Tax Return

A plain-English guide to IRS Form 1040 — what it's for, who files it, when it's due, and how to complete it.

Form number1040
Official nameU.S. Individual Income Tax Return
CategoryIndividual
Typically dueApril 15
Official IRS Form 1040 (PDF)

What is Form 1040?

Form 1040 is the main return almost every U.S. taxpayer files each year. It's where you report all your income, claim the standard or itemized deduction, apply credits, and figure whether you owe or get a refund.

Think of the 1040 as the summary sheet that pulls everything together. Income flows in from your W-2s and 1099s, adjustments and deductions come off, credits knock down the tax, and your payments (withholding plus any estimates) settle the score. Most of the complexity actually lives in the attached schedules — Schedule 1 for extra income and adjustments, Schedule 2 for other taxes, Schedule 3 for additional credits — while the 1040 itself stays surprisingly short.

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Who files it

Individuals and married couples with income above the filing threshold. Seniors can use the nearly identical Form 1040-SR with larger type.

When it's due

Form 1040 is generally due April 15. Deadlines can move for weekends and holidays, so confirm the exact date for the current year on IRS.gov.

Key lines and parts

Here's what you'll actually fill in on Form 1040:

  • Filing status and dependents (top of form)
  • Wages, interest, dividends and other income (lines 1–9)
  • Adjustments and AGI (lines 10–11)
  • Standard/itemized deduction and taxable income (lines 12–15)
  • Tax, credits, payments and refund or amount owed (lines 16–37)

How to file

File electronically for the fastest refund, or mail a paper return. Most people attach schedules (like Schedule 1, 2 or 3) for extra income, adjustments or credits.

Common mistakes & penalties

The classic errors are a wrong or transposed Social Security number, a filing status that costs you money (single instead of head of household), and forgetting a 1099 the IRS already has on file. Any of these can delay a refund or trigger an automated notice months later.
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Frequently asked questions

What is IRS Form 1040?

Form 1040 is the main return almost every U.S. taxpayer files each year. It's where you report all your income, claim the standard or itemized deduction, apply credits, and figure whether you owe or get a refund.

Who has to file Form 1040?

Individuals and married couples with income above the filing threshold. Seniors can use the nearly identical Form 1040-SR with larger type.

When is Form 1040 due?

Form 1040 is generally due April 15. Always confirm the current year's date on IRS.gov, since deadlines shift for weekends and holidays.

What's the most common mistake with Form 1040?

The classic errors are a wrong or transposed Social Security number, a filing status that costs you money (single instead of head of household), and forgetting a 1099 the IRS already has on file. Any of these can delay a refund or trigger an automated notice months later.