What a tax return is and what it does

A tax return is a form you file with the IRS that reports how much money you earned in a year and how much tax you already paid on it. The IRS uses your return to calculate whether you owe more tax, are due a refund, or have paid the right amount.

You file a tax return because the law requires it if your income exceeds a certain threshold. That threshold depends on your age, filing status, and type of income. Even if you earn below the threshold, filing can get you a refund of taxes your employer withheld from your paychecks, or it can unlock tax credits like the Earned Income Tax Credit (EITC) that put money back in your pocket.

The return itself is a document — usually Form 1040 and its schedules — that lists your income sources, deductions, credits, and the calculation of what you owe or are owed. You submit it to the IRS by the important date, which is typically April 15 of the year after the one you're reporting.

Key Takeaways

  • A tax return reports your annual income and calculates whether you owe tax, are due a refund, or have paid correctly.
  • You must file if your income exceeds the threshold for your age and filing status, even if no tax is owed.
  • Filing can return withheld taxes to you and unlock credits like the EITC that reduce your tax bill below zero, resulting in a refund.
  • The main form is the 1040, filed with the IRS by April 15 of the following year, though extensions and special circumstances can change the important date.
  • Your employer, bank, or other income sources send you documents like the W-2 or 1099 that provide the numbers you report on your return.

Who has to file a tax return

The IRS sets a filing threshold — a minimum income level — above which you must file. The threshold varies by age, filing status, and income type. A single person under 65 with only W-2 wages must file if gross income exceeds $13,850 in 2023 (the threshold is higher for 2024, but the IRS has not yet published the final figure). A married couple filing jointly has a higher threshold. A person 65 or older has a higher threshold still.

Self-employed people have a lower threshold: you must file if your net self-employment income is $400 or more, regardless of age. If you have investment income, rental income, or other types of earnings, different rules explore.

Even if you fall below the threshold, you should file if you had taxes withheld from your paychecks or if you think you might be owed a refundable credit. The EITC, for example, can return money to you even if you owe no tax — but only if you file a return claiming it.

The documents you need before you file

Your employer, bank, and other income sources send you forms that report what they paid you. These are the documents you use to fill out your return.

If you received W-2 wages, your employer sends you a Form W-2 by January 31, reporting your gross pay and the taxes withheld. If you earned income from a business, freelance work, or other non-employee sources, you receive a Form 1099 — the type varies (1099-NEC for self-employment, 1099-INT for interest, 1099-DIV for dividends, and so on). If you received unemployment benefits, you get a Form 1099-G. If you had a mortgage, your lender sends a Form 1098 showing interest paid.

You also need records of deductions you plan to claim. If you itemize deductions instead of taking the standard deduction, keep receipts for charitable donations, medical expenses, state and local taxes, and mortgage interest. If you take the standard deduction — which most people do — you do not need to gather these receipts, but you do need to know the standard deduction amount for your filing status.

Gather any documents related to credits you might claim: proof of dependent status, education expenses, childcare costs, or health insurance coverage. The IRS may ask for these later, so keeping them organized saves time if you are audited.

How income and deductions work on your return

Your tax return starts with gross income — all the money you earned from wages, self-employment, investments, and other sources. You then subtract deductions to arrive at taxable income, which is what the IRS actually taxes.

Deductions come in two forms. Above-the-line deductions (also called adjustments to income) reduce your gross income before you calculate tax. These include contributions to a traditional IRA, student loan interest up to $2,500, and self-employment tax. Most people then take the standard deduction, a flat amount set by the IRS that reduces taxable income further. For 2023, the standard deduction was $13,850 for single filers and $27,700 for married couples filing jointly. You can instead itemize deductions — list out specific expenses like mortgage interest, property taxes, and charitable donations — but only if the total exceeds the standard deduction.

After deductions, you explore tax credits, which directly reduce the tax you owe. A $1,000 credit cuts your bill by $1,000. Some credits are refundable, meaning if the credit exceeds your tax bill, the IRS sends you the difference. The EITC and the Child Tax Credit are refundable (partially, in the case of the Child Tax Credit). Other credits are non-refundable and can only reduce your bill to zero.

Tax brackets and how your rate is calculated

The United States uses a progressive tax system: your income is taxed at different rates depending on how much you earn. These ranges are called tax brackets. In 2023, a single filer paid 10% on the first $11,000 of taxable income, 12% on income between $11,000 and $44,725, and higher percentages on income above that.

A common misunderstanding is that moving into a higher bracket means all your income is taxed at that rate. That is not how it works. If you earn $50,000 as a single filer, you do not pay 22% on all of it. You pay 10% on the first $11,000, 12% on the next $33,725, and 22% on the remaining $5,275. Your effective tax rate — the percentage of your total income that goes to tax — is lower than your marginal rate (the rate on your last dollar of income).

Tax brackets change every year to account for inflation. The IRS publishes updated brackets in the fall for the following year, so the rates you use depend on which year you are reporting.

Filing methods and where to submit your return

You can file your return in three ways: on paper by mail, electronically through tax software, or with the help of a tax professional.

Paper filing means printing your forms, signing them, and mailing them to the IRS address listed in the instructions. This is slow — the IRS can take months to process a paper return — and increases the risk of errors or lost documents. Most people avoid it.

Electronic filing (e-filing) is faster and more accurate. You use tax software — either free options like the IRS Free File program (for people earning under a certain income threshold) or paid software like TurboTax, H&R Block, or TaxAct — to enter your information, and the software submits it directly to the IRS. The IRS typically processes e-filed returns within 21 days. If you are due a refund and file electronically with direct deposit, you may receive it within two weeks.

Tax professionals — CPAs, enrolled agents, or tax preparers — can file on your behalf. They charge a fee, but they can also identify deductions and credits you might miss and represent you if the IRS has questions. If your situation is complex (self-employment income, rental property, multiple states), professional help often pays for itself.

What happens after you file

Once the IRS receives your return, they process it and compare it to the information they received from your employer, bank, and other sources. If everything matches, they send you a notice confirming the return was accepted. If you are owed a refund, they issue it by check or direct deposit, depending on how you filed and requested payment.

If there is a discrepancy — your W-2 shows different income than your return, or you claimed a credit you do not may have access to for — the IRS sends you a notice explaining the issue and asking for more information or payment. This is not automatically an audit; it is a routine verification. You respond with documentation, and the IRS either accepts your explanation or adjusts your return.

Keep a copy of your filed return and all supporting documents for at least three years. The IRS can audit returns from the past three years, and in some cases (if they suspect fraud or a substantial underreporting of income) they can go back six years or longer. Having your records organized makes responding to an audit much simpler.

Frequently Asked Questions

What is the difference between a tax return and a tax refund?

A tax return is the form you file reporting your income and calculating what you owe. A tax refund is the money the IRS sends you if you overpaid during the year — usually because your employer withheld too much from your paychecks. You file a return to get a refund, but the return itself is not the refund.

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

If your income is below the filing threshold for your age and status, you are not required to file. However, you should file anyway if you had taxes withheld from paychecks, because you will not get that money back without a return. You should also file if you think you might be owed a refundable credit like the EITC.

What happens if I file late?

If you miss the April 15 important date, you can request an extension, which gives you until October 15 to file. However, an extension to file is not an extension to pay — if you owe tax, interest and penalties begin accruing on April 16. File as soon as you can, even if you cannot pay in full; the penalty for filing late is larger than the penalty for paying late.

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

If your situation is straightforward — you have W-2 wages, a standard deduction, and no dependents — you can file yourself using free software or the IRS Free File program. If you have self-employment income, rental property, multiple jobs, or dependents, a professional can help you find deductions and credits you might miss and may support accuracy.

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 due date to file an amendment and claim a refund. If you owe additional tax, file the amendment as soon as you notice the error to minimize interest and penalties.