Extended tax deadline: Finishing your taxes and what happens if you miss it
At a glance
- October 15 is the final extended tax deadline to file your return if you requested an extension with Form 4868.
- If you miss the October extended tax filing deadline, you’ll have failure-to-file penalties and, potentially, failure-to-pay penalties if you still owe taxes.
- To minimize penalties, file your return immediately, pay as much as you can, explore IRS payment plans, and check if you qualify for penalty relief.
The October extended tax deadline can almost feel like a second tax season. If you filed for an extension before the April 15 deadline and are just getting started on your return, the rush to get taxes done before October 15 deadline is real.
But with two different deadlines and terms floating around—like “extended tax deadline” and “late filing penalty” and more—it’s easy to feel overwhelmed. Plus the process can get confusing as an extension gives your more time to file, not more time to pay your taxes.
We’re here to break it down so you know exactly what to expect and what to do if you’re running behind. Read on to get all your tax extension deadline questions answered.
Of course, you can rely on H&R Block to get your return across the finish line whether you file online or with an H&R Block tax pro.
What is the the last day to file taxes on extension?
The last day to file taxes on extension is October 15. This extended tax deadline applies to taxpayers who submitted Form 4868 to request an automatic six-month extension before their tax deadline in April.
While you have until October 15 to file your tax return, any taxes owed must be paid by the original due date to avoid interest and penalties. The extension only prevents the failure to file penalty.
However, if you didn’t file that extension form in April and you haven’t yet filed your 2025 taxes, you’ll want to get it done as soon as possible. Check out our next steps section below to get started.
Please also note some taxpayers may have extra time to file their tax returns and pay any taxes due.
- You may have more time if you are a:
- Victim of a federally declared disaster victim
- Member of the military personnel serving in a combat zone, or
- Living abroad
Can I file for another extension after October 15?
No, unfortunately, you can’t file for a second tax extension after October 15. The IRS only allows one automatic extension per tax year. If you miss this deadline, your return is considered late, and penalties may apply.
If you do not pay your taxes by the original due date, you will be subject to interest and penalties. The extension to file does not prevent these charges from accruing.
However, there are still ways to get caught up and minimize the impact. Check out the next steps section below.
Don’t owe taxes this year? You may not need an extension. If you’re generally only required to file a return by the deadline if you owe taxes. If you’re expecting a refund, you may not be required to file a return—but, keep in mind, filing is the only way to get your refund.
What happens if you miss the tax extension deadline?
If you miss the October extended tax filing deadline, you’ll have failure-to-file penalties that are retroactive to your original filing date (typically October 15) and, potentially, failure-to-pay penalties retroactive to the original payment due date (typically April 15) if you still owe taxes.
Your best bet is to file your tax return as soon as possible after you missed the tax extension deadline of October 15, 2025, to minimize any further penalties and interest.
Failure-to-File Penalty
This penalty is typically 5% of the unpaid taxes for each month your return is late, up to a maximum of 25%. If your return is more than 60 days late, the minimum penalty is either $510 (for 2025) or 100% of the tax due—whichever is less.
Some people may think of this as a late filing penalty after the extension, but the technical term is failure-to-file penalty.
Failure-to-Pay Penalty and interest
If you owe taxes and don’t pay by the extended tax deadline in October, the IRS charges a failure-to-pay penalty of 0.5% per month on the unpaid amount. Interest also accrues daily, based on the federal short-term rate plus 3%.
How the penalties are calculated
Penalties are calculated based on how late your return is and how much you owe. If both the failure-to-file and failure-to-pay penalties apply, the IRS reduces the failure-to-file penalty by the amount of the failure-to-pay penalty so that the combined penalties do not exceed 5% per month. After 5 months, the failure to file penalty will max out but the failure to pay penalty will continue.
You missed the deadline: What are your next steps for filing taxes after October 15?
Missing the extended deadline isn’t the end of the world, but you do want to act sooner than later.
Here’s what you can do to get back on track:
- File your return immediately to minimize penalties. The sooner you file, the less you’ll owe in penalties. Even if you can’t pay your full tax bill, filing your return stops the failure-to-file penalty from growing.
- Pay as much of your tax bill as possible. Paying even a portion of your tax liability can reduce the failure-to-pay penalty and interest. Every dollar counts.
- Explore IRS payment options for your balance. If you can’t pay in full, the IRS offers payment plans, there are options if you’re unable to pay your tax bill. You can request an IRS payment plan, which allows you to pay your taxes in installments. Find out more about setting up an installment agreement.
- Explore whether you qualify for penalty relief. If you acted in good faith and have a valid reason for not meeting your tax obligations, you can ask the IRS to remove or reduce some penalties. If you think the amount you owe is incorrect, you can dispute the penalty. Additionally, if this is your first tax penalty or you meet other specific criteria, you might qualify for relief through an administrative waiver.
Extended tax deadline FAQs
Can I file my taxes now if I’m on an extension?
Yes! If you filed for an extension and haven’t submitted your return yet, you can do it any time before the extended tax filing deadline of October 15. After that, your return is considered late.
What’s the difference between an extension to file and an extension to pay?
An “extension to file” gives you more time to submit your return (typically extended to October 15), but it doesn’t extend your deadline to pay taxes. Unfortunately, there isn’t a way to get an “extension to pay” your taxes. Any unpaid taxes after April 15 may accrue penalties and interest.
Will I lose my refund if I miss the October 15 deadline?
Not necessarily. You have up to three years from the original due date to claim a refund. However, if you wait too long, you could forfeit it.
Keep in mind if you’re generally only required to file a return by the deadline if you owe taxes. If you are expecting a refund, you may not be required to file a return, but filing is the only way to access your refund.
Get help filing your tax return from H&R Block
While taxes can be stressful, you don’t have to go it alone. Whether you work with a tax professional or file online, you can trust the expertise of H&R Block to help you file your taxes.
Make an appointment to file with a tax pro or file taxes online with H&R Block Online today!
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