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

The IRS typically begins accepting returns in late January and stops accepting paper returns on April 15. Electronic returns can sometimes be filed after April 15 if you request an automatic extension, but the deadline to file without penalty is still April 15 unless you have filed for an extension beforehand. The exact start date shifts slightly each year depending on when the IRS finishes testing its systems and when January 31 falls on a weekday.

For 2024, the IRS began accepting returns on January 29. For 2025, the start date is January 27. These dates are published by the IRS in the fall of the prior year, so you can plan ahead. The April 15 deadline is fixed by law and does not move unless it falls on a weekend or federal holiday — in those cases, the deadline shifts to the next business day.

Key Takeaways

  • The IRS opens its filing season in late January each year, with the exact date announced in the fall of the prior year.
  • April 15 is the deadline to file your return or request an extension, and this date is set by law, not by IRS choice.
  • If you file electronically and request an automatic extension before April 15, you have until October 15 to submit your return, though taxes owed are still due by April 15.
  • Paper returns must arrive at the IRS by April 15; electronic returns can be filed later if you have an approved extension.
  • If April 15 falls on a weekend or federal holiday, the deadline moves to the next business day.

Why the IRS does not open earlier in January

The IRS needs time after December 31 to receive and process forms from employers, banks, and other institutions that report your income. W-2 forms from employers must be sent to employees by January 31, and the IRS receives its own copies on the same schedule. Until those forms arrive and are entered into IRS systems, the agency cannot safely process returns that depend on matching your reported income to what employers reported.

The IRS also uses the weeks before the filing season to test its computer systems, train staff, and prepare for the volume of returns it will receive. Opening too early would mean processing returns based on incomplete income data, which creates errors and delays refunds. The late January start date balances the need for complete information against taxpayer demand to file early.

What happens if you file before the season opens

If you submit a return electronically before the IRS filing season begins, the return will be rejected. You will receive an error message telling you to resubmit after the season opens. Paper returns submitted before the season opens will be held and processed once the season begins, but this creates delays in receiving your refund.

The safest approach is to wait until the official start date to file electronically. If you are filing on paper and want to ensure your return is in the IRS mailbox by April 15, you should mail it by early April to account for postal delays. The IRS date-stamps returns based on the postmark, not the date received, so a return postmarked April 15 counts as timely even if it arrives in May.

How extensions work and what they do and do not cover

An automatic extension gives you until October 15 to file your return, but it does not extend the deadline to pay taxes owed. If you owe money, it is due by April 15 regardless of whether you have filed. Paying late incurs interest and penalties, even if you filed an extension.

To request an extension, you file Form 4868 (Application for Automatic Extension of Time to File U.S. Individual Income Tax Return) by April 15. You can file this form electronically through tax software or by mail. The extension is automatic — the IRS does not review it or deny it. Once you file Form 4868, you have until October 15 to submit your actual return without penalty for late filing.

An extension is useful if you are waiting for documents, need time to gather records, or are unsure of your tax situation. It is not useful for avoiding payment of taxes owed. If you think you will owe money, estimate what you owe and pay it by April 15, then file your return (or extension) later with the actual numbers.

State tax deadlines and how they differ from federal

Most states follow the federal April 15 deadline, but some states have different dates or different rules. A few states do not have income tax at all. Some states allow extensions that run longer than October 15. You need to check your state's tax agency website for the specific deadline in your state, because missing a state deadline can result in state penalties even if you filed your federal return on time.

If you file a federal extension on Form 4868, some states automatically grant you an extension as well, but not all. A few states require you to file a separate extension form. The safest approach is to check your state's rules before April 15 if you think you will need more time.

What to do if you miss the April 15 deadline

If you do not file by April 15 and did not file an extension, you will owe a failure-to-file penalty in addition to any taxes owed. The penalty is usually 5 percent of the unpaid tax for each month the return is late, up to 25 percent. You will also owe interest on the unpaid tax, calculated from April 15 forward.

If you realize you have missed the deadline, file your return as soon as possible. The sooner you file, the less interest accrues. If you cannot pay what you owe, you can set up a payment plan with the IRS. The IRS also has programs for taxpayers facing financial hardship. Filing late is better than not filing at all, because not filing makes the penalties larger and can trigger additional IRS action.

When the IRS closes to new returns near the end of the season

The IRS does not formally close to new returns on April 15, but returns postmarked after April 15 are considered late. If you are filing electronically, your return must be transmitted to the IRS by 11:59 p.m. Eastern time on April 15 to be considered timely. If you are filing on paper, the postmark date is what matters — a return postmarked April 15 is timely even if it arrives weeks later.

Some tax software companies and tax preparers close their systems before April 15 to allow time for final processing and transmission to the IRS. If you are using a tax preparer, ask them when they stop accepting new returns. If you are filing yourself, do not wait until April 14 or 15 to start — filing in March gives you time to fix errors and ensures your return reaches the IRS without last-minute problems.

Frequently Asked Questions

Can I file my taxes in December for the next year?

No. The IRS does not accept returns for a tax year until the filing season for that year opens, which is always after December 31. A return filed in December for the next year will be rejected. You must wait until late January of the following year to file.

What if April 15 falls on a Saturday or Sunday?

If April 15 falls on a Saturday, the deadline moves to Monday, April 17. If it falls on a Sunday, the deadline moves to Monday, April 16. If April 15 falls on a weekday that is a federal holiday (rare but possible), the deadline moves to the next business day. The IRS announces any deadline shifts in advance.

Do I have to file during the official filing season?

No. You can file anytime after the season opens and before April 15. Filing early means you receive your refund sooner if you are owed money. Filing late in the season (March or early April) is riskier because software glitches or mail delays could cause you to miss the deadline.

If I file an extension, can I file my return anytime before October 15?

Yes. Once you file Form 4868, you can submit your return anytime between the extension filing date and October 15 without penalty for late filing. However, if you owe taxes, they are still due by April 15, and you will owe interest on any unpaid amount from April 15 to the date you pay.