The IRS filing season runs from late January through mid-April most years

The IRS typically begins accepting tax returns in late January and stops accepting them on April 15 (or the next business day if April 15 falls on a weekend or holiday). This window is when the IRS's systems are fully staffed and processing returns at normal speed. Returns filed after April 15 are considered late, and you may owe penalties and interest on any taxes you still owe, even if you are due a refund.

The exact start date shifts slightly each year because the IRS needs time to update its systems for new tax laws and forms. In 2024, the IRS began accepting returns on January 29. In 2025, it began on January 27. You can find the current year's start date on IRS.gov, but it is always in late January.

If you file after April 15, you must still file — the deadline does not disappear. The IRS will calculate penalties based on how late you file and how much tax you owe. If you are due a refund, there is no penalty for filing late, but you lose the refund if you wait more than three years.

Key Takeaways

  • The IRS accepts returns from late January through April 15 each year, with the exact start date announced in advance on IRS.gov.
  • Filing after April 15 does not erase the deadline — you still must file, and you will owe penalties and interest if you owe taxes.
  • If you cannot file by April 15, you can request an automatic six-month extension, which moves your deadline to October 15 but does not extend the time to pay taxes owed.
  • The IRS processes returns faster earlier in the season; filing in February or early March usually means a faster refund than filing in late March or April.

How to request an extension if you cannot file by April 15

You do not need a reason to request an extension. You can file Form 4868 (Application for Automatic Extension of Time To File U.S. Individual Income Tax Return) with the IRS, and you will automatically receive six additional months. This moves your filing deadline to October 15.

You can file Form 4868 on paper by mail, electronically through tax software, or through a tax professional. If you file electronically, you get confirmation immediately. The form is simple — it asks for your name, address, and estimated tax liability. You do not have to explain why you need the extension.

Important: an extension to file is not an extension to pay. If you owe taxes, they are still due on April 15, even if you file your return in October. If you cannot pay by April 15, you can set up a payment plan with the IRS, but interest and penalties will accrue on the unpaid balance from April 15 onward.

Why the IRS stops accepting returns on April 15

April 15 is the statutory deadline set by federal tax law. The IRS cannot legally accept a return filed after this date unless you have filed Form 4868 before April 15 to request an extension. The deadline exists so the government can collect taxes owed and process refunds within a predictable timeframe.

The IRS also uses the April 15 deadline to manage its workload. Tax season is the busiest time of year for the agency. After April 15, the IRS shifts focus to processing the returns already filed, answering taxpayer questions, and handling audits. If the deadline were open-ended, the IRS would never finish processing one year's returns before the next year's season began.

What happens if you miss the April 15 deadline without an extension

If you file after April 15 without having requested an extension beforehand, the IRS will charge you a failure-to-file penalty. This penalty is usually 5% of the unpaid tax for each month (or part of a month) that your return is late, up to a maximum of 25%. If you owe $1,000 in taxes and file two months late, the penalty could be around $100.

You will also owe interest on any unpaid taxes from April 15 until you pay. The interest rate is set quarterly by the IRS and is currently around 8% per year, though it changes. Interest compounds daily.

If you are due a refund, there is no failure-to-file penalty, but you will lose the refund if you wait more than three years to file. For example, if you are due a $500 refund for 2024 and do not file until 2028, the IRS will keep the $500.

How filing early affects your refund timeline

The IRS processes returns in the order they are received, but not all returns move at the same speed. Returns filed in late January and February are typically processed within 21 days. Returns filed in March and early April take longer because the volume is higher. Returns filed in the last week of March or in April can take four to six weeks or longer.

If you are due a refund, filing early means you receive it sooner. If you owe taxes, filing early gives you more time to arrange payment before April 15. There is no advantage to waiting until late March or April to file.

Some returns are flagged for review during processing, which delays the refund. This can happen for many reasons — a math error, a missing form, or a mismatch between your return and information the IRS has on file (such as income reported by your employer). If your return is reviewed, the IRS will contact you by mail.

State tax return deadlines and the federal deadline

Most states follow the federal April 15 deadline for income tax returns. However, a few states have different deadlines or do not have income tax at all. If you live in a state with income tax, check your state's tax agency website for the exact deadline in your state.

If you file a federal extension with Form 4868, most states will automatically extend your state return deadline as well. However, some states require a separate extension form. If you are unsure, contact your state's tax agency or ask your tax preparer.

Frequently Asked Questions

Can I file my tax return before the IRS starts accepting them in January?

No. If you file before the IRS begins accepting returns, the return will be rejected. You must wait until the IRS opens its filing season, which is announced in advance on IRS.gov. Most tax software will not let you file before the season opens.

What if April 15 falls on a weekend or holiday?

The deadline moves to the next business day. For example, if April 15 is a Saturday, the deadline becomes Monday, April 17. The IRS announces the exact deadline date each year on IRS.gov.

Do I need to file a return if I do not owe taxes?

If you had taxes withheld from your paychecks or made estimated tax payments, you should file to get a refund. If you are due a refund and do not file within three years, you lose it. If you owe nothing and had nothing withheld, you are not required to file, but there is no penalty for filing anyway.

Can the IRS extend the April 15 deadline for everyone?

The IRS can extend the deadline for specific areas affected by disasters (hurricanes, floods, wildfires). If your area is affected, the IRS will announce an extension on IRS.gov. For most taxpayers in most years, the deadline remains April 15.

What if I file my return but do not pay the taxes I owe by April 15?

Interest and penalties begin accruing on April 15 on any unpaid balance. You can set up a payment plan with the IRS to pay over time, but interest and penalties will continue to grow. The sooner you pay, the less interest you will owe.