An income tax return is a form you send to the IRS that reports how much money you earned and how much tax you owe

The IRS — the Internal Revenue Service, the federal tax agency — uses your return to check whether you paid the right amount of tax during the year. If your employer or bank withheld too much, you get a refund. If you didn't pay enough, you owe the difference. A return is also how you claim deductions and credits that lower your tax bill.

Most people file a return once a year, usually between January and April 15. You file for the previous calendar year — so in 2024, you file a return for the money you earned in 2023. The form itself is called a 1040 if you're filing as an individual, though you may also file a 1040-SR if you're 65 or older, or a different form if you're self-employed or have a business.

Filing is required if your income exceeds a certain threshold, which changes each year and depends on your age and filing status. Even if you're not required to file, you may want to — especially if your employer withheld taxes and you're owed a refund.

Key Takeaways

  • An income tax return reports your earnings to the IRS and shows whether you paid the correct amount of tax during the year.
  • You file a return for the previous calendar year, usually between January and April 15.
  • The main form is the 1040, though the IRS offers a shorter version (1040-SR) for people 65 and older.
  • Filing is required only if your income exceeds a threshold set by the IRS, but filing anyway can get you a refund if taxes were withheld from your pay.

What information goes on your return

Your return lists all the income you received during the year. This includes wages from a job (reported on a W-2 form your employer sends you), interest from a bank account, dividends from investments, self-employment income, rental income, and other sources. You report the total, then subtract deductions to arrive at your taxable income — the amount the IRS actually taxes.

Deductions come in two types. A standard deduction is a flat amount the IRS lets everyone subtract; for 2023, it was $13,850 for a single filer, though it changes yearly and varies by age and filing status. A itemized deduction means you add up specific expenses — mortgage interest, property taxes, charitable donations, medical bills — and subtract that total instead if it's larger than the standard deduction.

You also report any tax credits you're may have access to to. Unlike deductions, which reduce your taxable income, credits reduce the tax itself dollar-for-dollar. Common credits include the Earned Income Tax Credit (EITC) for lower-income workers and the Child Tax Credit for parents.

How withholding and refunds work

When you work for an employer, they withhold money from each paycheck and send it to the IRS on your behalf. The amount withheld is an estimate based on a form you fill out called a W-4. If your employer withholds too much, you'll overpay your tax for the year. When you file your return, the IRS calculates what you actually owe, compares it to what was withheld, and sends you the difference as a refund.

If your employer withheld too little, you'll owe money when you file. You can pay it with your return or set up a payment plan with the IRS if you can't pay in full. Self-employed people and those with other income sources don't have withholding, so they often owe at tax time unless they've made estimated tax payments throughout the year.

The size of your refund depends on how accurately your W-4 reflects your actual tax situation. If you claim too many allowances on your W-4, less is withheld and you may owe. If you claim too few, more is withheld and you'll get a larger refund — though that means you gave the government an interest-free loan all year.

Who has to file and when

The IRS requires you to file if your income exceeds a threshold. For 2023, a single person under 65 had to file if they earned more than $13,850 in wages. The threshold is higher if you're 65 or older, married, self-employed, or have other income sources. The IRS publishes updated thresholds each year on its website.

Even if you're below the threshold, you should file if you had taxes withheld from your pay and expect a refund. You should also file if you're self-employed and owe self-employment tax, or if you're claiming a refundable credit like the EITC — the IRS will only send you that money if you file.

The important date to file is April 15 of the year following the tax year, though you can request an extension to October 15 if you need more time. Filing early — as soon as you have all your documents — can speed up your refund if you're owed one.

How to file your return

You have three main options. You can use tax software — programs like TurboTax, H&R Block, or TaxAct walk you through the questions and fill out your forms for you. You can work with a tax professional, such as a CPA or enrolled agent, who prepares the return for you. Or you can fill out the forms by hand and mail them to the IRS, though this is slower and more error-prone.

The IRS also offers Free File, a program that lets people below a certain income threshold (usually around $60,000) use tax software at no cost. You access it through the IRS website. If you can't afford paid software and don't may have access to for Free File, many nonprofits and libraries offer free tax preparation help through the Volunteer Income Tax information (VITA) program.

Whichever method you choose, you'll need documents on hand: your W-2 forms from employers, 1099 forms for other income, receipts for deductions if you itemize, and information about any credits you're claiming. Employers and financial institutions must send you these forms by January 31.

What happens after you file

Once you file, the IRS processes your return. If you file electronically and claim a refund, the IRS typically issues it within 21 days, though it can take longer if there are errors or if the IRS needs to verify information. If you owe money, you can pay when you file or arrange a payment plan.

The IRS may contact you if there's a discrepancy between what you reported and what employers or financial institutions reported about your income. This is called a notice, and it usually means you owe additional tax, a penalty, or interest. You have the right to respond and explain your position.

Keep a copy of your filed return and all supporting documents for at least three years. The IRS can audit your return during that time, meaning they'll ask you to prove the income and deductions you claimed. Keeping good records makes it easier to respond if that happens.

Self-employed and business owners

If you're self-employed — you work for yourself rather than for an employer — you file a different form. You'll use Schedule C to report your business income and expenses, then attach it to your 1040. You'll also file Schedule SE to calculate self-employment tax, which covers Social Security and Medicare. Self-employed people pay both the employee and employer portions of these taxes, roughly 15.3% of net income.

Self-employed filers don't have withholding, so you're responsible for sending the IRS estimated tax payments four times a year — usually in April, June, September, and January. These payments are based on your expected annual income and tax. If you don't make these payments and owe a large amount at tax time, you may face penalties and interest.

Frequently Asked Questions

What's the difference between a tax return and a tax refund?

A tax return is the form you file with the IRS reporting your income and tax. A tax refund is money the IRS sends you if you overpaid your taxes during the year. You only get a refund if you file a return and the IRS determines you paid more than you owed.

Do I have to file if I didn't earn much money?

Not if your income is below the IRS threshold for your filing status and age. However, if your employer withheld taxes from your pay, filing will get you a refund. If you're self-employed or have other income, the rules are different — check the IRS website or speak with a tax professional.

What happens if I file late?

If you owe taxes and file after April 15, you'll owe a failure-to-file penalty and interest on the unpaid amount. If you're owed a refund, there's no penalty for filing late, but you can only claim the refund for three years after the original important date. You can request an extension to October 15 if you need more time.

Can I file my return myself, or do I need a professional?

You can file yourself using tax software, by hand, or with help from a free tax preparation program. You only need a professional if your situation is complex — you own a business, have rental income, or are dealing with a complicated investment situation. For most people, software or free help is sufficient.

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

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