What is form 1040? A complete guide to the U.S. Individual Income Tax Return

Learn what the 1040 tax form is, which attachments you need, and how you can fill and sign your tax forms digitally.

Form 1040, officially called the U.S. Individual Income Tax Return, is the primary IRS form Americans use to report their annual income, claim deductions and credits, and calculate how much tax they owe or how much they’ll receive as a refund. Whether you file taxes (keep the link here on "file taxes") yourself or work with a tax professional, understanding Form 1040 is essential for accurate, stress‑free tax preparation.

This guide explains what the 1040 form is, who needs to file it, how to get it, which schedules you may need, and how to complete and sign it digitally.

What is a 1040 form used for?

Form 1040 is the standard federal income tax form for U.S. residents. You use it to:

• Report your income
• Claim deductions and tax credits
• Calculate your tax liability
• Determine your refund
• Report additional taxes (self‑employment, retirement plan taxes, etc.)

Every individual taxpayer who meets the minimum income threshold for their filing status must file a 1040 each year.

Be sure to check out our tax document checklist to know which forms are needed to file taxes this year.

How to get a 1040 IRS form.

You can access Form 1040 in several ways:

• Download a fillable PDF directly from the IRS website (keep the link here)
• Retrieve past 1040 forms through your IRS online account
• Receive the form from your tax preparer
• Use tax software that automatically generates the form

Once downloaded, you can fill and sign the PDF using Adobe Acrobat.

How to fill out Form 1040.

The IRS website has detailed instructions for how to fill in Form 1040. You can also download a PDF version of 1040 that you can fill with PDF editing software like Adobe Acrobat:

1. Open the 1040 PDF form in Acrobat and type in your information.
2. Remember also to check the correct tick boxes.
3. Once you’ve finished filling out the form, you can sign it digitally with the Fill and Sign tool.

You can also easily fill and sign a PDF of your 1040 with Adobe Acrobat online services.

Who needs to file an IRS 1040 form?

All United States citizens and permanent residents earning at least the minimum income for their filing status must file a 1040 form. The minimum differs depending on whether you are over or under 65 years old, and it could change each year. Visit the IRS website to find out the minimum income depending on whether you are single, head of household, married filing jointly or separately, or a qualifying surviving spouse.

Why Form 1040 is important

The 1040 form is one of the primary forms required for filing your taxes. Filing Form 1040 ensures you:

• Comply with federal tax law
• Avoid penalties and interest
• Qualify for refunds
• Build Social Security and Medicare credits
• Provide income verification for loans, financial aid, and government programs
• Maintain accurate financial records

Failing to file when required can result in penalties or legal consequences.

How often do I need to file the 1040 tax form?

You’ll need to file the 1040 form every year before the tax filing deadline, which is usually April 15.

What are 1040 schedules?

Tax schedules are attachment forms that may be required to calculate and report different sources of income or deductions. There are 20 possible schedules, each designed for different kinds of information. For example, if you don’t want to take the standard deduction, you can use Schedule A to itemize deductions.

Schedule 1 — Additional income and adjustments

Because the 1040 form doesn’t have many lines for reporting different income types, some taxpayers need an additional form to list income from different sources, such as unemployment compensation, alimony, farm income, or gambling winnings.

Schedule 2 — Additional taxes

With Schedule 2, you can report any additional taxes you owe, such as:

• Self‑employment tax
• Taxes on retirement plans
• Alternative minimum tax

Schedule 3 — Additional credits

This schedule is used to claim credits not listed directly on Form 1040, such as:

• Foreign tax credit
• General business credit
• Education credits

How is a 1099 form different from a 1040 form?

The 1040 helps calculate the tax you owe based on your entire income. In contrast, a 1099 form is used for each separate source of income. If you are a contractor or self-employed, you’ll receive payments from different entities rather than a single employer. You’ll need a separate 1099 for each source, but you’ll add it all together in the 1040 form.

How to prepare Form 1040 in simple steps

Filing your taxes doesn’t have to feel overwhelming, especially when you break the process into clear, manageable steps. Whether you’re filing on your own or gathering documents for a tax professional, understanding the basic flow of completing Form 1040 can make the entire experience faster, easier, and far more accurate. The outline below walks you through the simplest way to prepare your 1040 from start to finish.

1. Gather all tax documents.
2. Digitize and organize them.
3. Enter your personal information.
4. Report all income.
5. Claim deductions and credits.
6. Calculate your tax or refund.
7. Sign and file your 1040.
8. Save a digital copy for your records.

More resources for finances and tax forms.

After learning what a 1040 form is, explore these additional tax-related resources:

• Learn how to scan receipts for taxes.
• Learn about the IRS Form 4868 for tax extensions.
• Learn about the IRS Form 8822: Change of address.
• Find out what a cash flow budget is.
• Create a budget planning worksheet template.

Find out more about working with PDFs online. Discover everything you can do with Acrobat to fill, convert, and share PDFs today.