The 1040 is the main form you use to report your income to the IRS

The Form 1040 is the federal income tax return form. You file it every year to tell the IRS how much money you made, what deductions you can claim, and how much tax you owe or should get back. Almost every person who earns income in the United States files a 1040 or a variation of it.

The IRS uses your 1040 to calculate whether you paid enough tax throughout the year. If you paid too much (usually through paycheck withholding), you get a refund. If you paid too little, you owe the difference. The form itself is just the vehicle — it collects information the IRS already has from your employer, bank, and investment accounts, and it lets you report income they might not know about.

Key Takeaways

  • The 1040 reports all your income sources — wages, self-employment, interest, dividends, rental income — to the IRS in one place.
  • You file a 1040 (or a shorter version like the 1040-SR for people 65 and older) if you earned above a certain threshold, even if no tax is owed.
  • The form asks for personal information, income totals, deductions, and tax credits that reduce what you owe.
  • Most people file between January 2 and April 15 each year, though you can file earlier once tax documents arrive from employers and financial institutions.

What income you report on the 1040

The 1040 has sections for different types of income. Wages and salary go in one section — this is money from a job, reported on a W-2 form your employer sends you. Self-employment income (money from running your own business or freelance work) goes in another section and requires you to file a Schedule C form alongside the 1040. Interest and dividends from savings accounts and investments are reported separately. Capital gains (profit from selling stocks or property) have their own section.

You also report income that does not come with a tax form: cash tips, prizes, gambling winnings, or money from selling personal items. If you received unemployment benefits, Social Security, or other government payments, those appear on the 1040 too. The form totals all these sources to show your gross income — the starting point before deductions.

Deductions and credits that lower your tax bill

The 1040 lets you reduce your taxable income in two ways. Deductions lower the amount of income that gets taxed. You can either take the standard deduction (a flat amount set by the IRS each year that varies by age and filing status) or itemize deductions (add up specific expenses like mortgage interest, property taxes, or charitable donations). Most people take the standard deduction because it is simpler and often larger.

Tax credits are different — they reduce the actual tax you owe, dollar for dollar. The Earned Income Tax Credit (EITC), Child Tax Credit, and education credits are common examples. A $1,000 credit saves you $1,000 in tax; a $1,000 deduction saves you tax only on that $1,000 of income. The 1040 has lines for the credits you are may have access to to claim.

Who has to file a 1040

You must file if your income exceeds a threshold set by the IRS. That threshold depends on your age, filing status (single, married, head of household), and whether you are claimed as a dependent. For 2024, a single person under 65 must file if they earned more than $14,600 in wages. A married couple filing jointly must file if combined income exceeded $29,200. These numbers change each year.

Even if you earned less than the threshold, you should file if you had taxes withheld from your paychecks — you will likely get a refund. You should also file if you are owed a refundable credit like the EITC, which can result in money back even if you owe no tax. Self-employed people must file if net earnings from self-employment were $400 or more.

The 1040 and its shorter versions

The standard 1040 is two pages and works for most people. The IRS also offers Form 1040-SR for people age 65 and older — it has the same information but larger print and slightly different line arrangements. Neither is "shorter" in the sense of asking fewer questions; they are just formatted differently.

In the past, the IRS offered forms like the 1040-EZ and 1040-A for simpler situations, but those were discontinued after 2017. Now everyone uses the same 1040, though you may not need to fill in every line. If you have no self-employment income, you skip the self-employment section. If you have no investment income, you skip that section. You only complete the parts that apply to you.

Schedules and attachments that go with the 1040

The 1040 itself is the main form, but you often attach additional forms called schedules. Schedule C is for self-employment income and expenses. Schedule 1 reports other income sources like rental income, prizes, or farm income. Schedule A is used if you itemize deductions instead of taking the standard deduction. Schedule D reports capital gains and losses from investments.

You also attach forms that come from other people or institutions: your W-2 from your employer, 1099 forms from banks (1099-INT for interest), investment firms (1099-DIV for dividends), or clients who paid you as a contractor (1099-NEC or 1099-MISC). These forms tell the IRS what income they have already recorded, so the IRS can check that your 1040 matches. You do not mail these forms to the IRS — you keep them for your records — but you must report the income they show.

When and how to file your 1040

The tax year runs January 1 through December 31. You file your 1040 for that year between January 2 and April 15 of the following year. The IRS begins accepting returns in early January, once employers and financial institutions have sent out W-2s and 1099 forms. You cannot file before you have those documents — the IRS will reject an incomplete return.

You can file on paper by mailing the form to the IRS address listed in the instructions, or you can file electronically using tax software or a tax preparer. Electronic filing is faster and more accurate — the IRS processes e-filed returns in about 21 days if you choose direct deposit for any refund. If you cannot file by April 15, you can request an extension, which gives you until October 15 to file, though any tax owed is still due by April 15.

Frequently Asked Questions

Do I have to file a 1040 if I did not earn much money?

Only if your income exceeded the IRS threshold for your age and filing status. However, if your employer withheld taxes from your paychecks, you should file to get that money back as a refund. If you earned less than the threshold but are owed a refundable credit like the EITC, filing gets you that credit.

What happens if I file my 1040 late?

If you owe tax, the IRS charges penalties and interest on the unpaid amount. If you are getting a refund, there is no penalty for filing late, but you cannot claim the refund after three years. If you cannot file by April 15, request an extension before the deadline — it postpones the filing deadline to October 15 but does not postpone the tax payment deadline.

Can I file a 1040 if I am self-employed?

Yes. Self-employed people file the same 1040 as everyone else, but they also attach Schedule C to report business income and expenses. You must file if net self-employment income was $400 or more, even if you owe no income tax, because you owe self-employment tax (Social Security and Medicare tax).

What if I made a mistake on my 1040 after I filed it?

You can file an amended return using Form 1040-X. You have three years from the original due date to file an amendment. If the mistake means you owe more tax, file as soon as you notice it to avoid additional penalties and interest.