How to file a tax extension online
You file a tax extension online through the IRS website using Form 4868, which gives you six additional months to submit your tax return. The IRS accepts extensions filed electronically through their Free File program, through tax software, or through a tax professional's account. Filing online takes about 15 minutes and you receive confirmation immediately — you do not have to mail anything or wait for a response.
An extension postpones your filing deadline but not your payment deadline. If you owe taxes, the IRS expects payment by the original deadline (usually April 15) even if your return is not due until October 15. Filing an extension without paying what you estimate you owe will result in interest and penalties on the unpaid balance.
Key Takeaways
- Form 4868 filed online extends your filing deadline from April 15 to October 15, but does not extend your payment deadline if you owe taxes.
- You can file an extension through IRS Free File, commercial tax software, or a tax professional's online account without mailing anything.
- Filing an extension costs nothing and takes about 15 minutes; you receive confirmation on screen immediately.
- If you owe taxes, you must estimate the amount and pay it by April 15 even if you file an extension, or you will owe interest and penalties.
- You can file an extension up until the original tax deadline; filing after that date means you have filed late.
Filing through IRS Free File
The IRS Free File program lets you file Form 4868 at no cost if your income is below a certain threshold. For the 2024 tax year, that threshold is $79,000 for most filers. You go to IRS.gov, click on Free File, and choose from a list of IRS-approved tax software providers that offer free filing to people within the income limit.
Once you select a provider and create an account, you enter your basic information (name, Social Security number, address, filing status) and then select the option to file Form 4868. The software walks you through a short form asking whether you expect a refund or owe taxes, and if you owe, it asks you to estimate the amount. You then review your form, sign it electronically, and submit it. The IRS confirms receipt on screen, and you can print or save a copy for your records.
Filing through tax software
Most commercial tax software — TurboTax, H&R Block, TaxAct, and others — includes the option to file Form 4868 as part of their standard package. You do not have to purchase the full tax return preparation to file an extension; many providers offer a standalone extension filing for $0 to $15.
Open the software, select "file an extension" or "Form 4868" from the menu, and enter your name, Social Security number, address, and filing status. The software asks whether you expect a refund or owe taxes. If you owe, estimate the amount and enter it. Review the form, sign electronically, and submit. The software sends it directly to the IRS and shows you a confirmation number on screen.
Filing through a tax professional
If you work with a CPA, tax attorney, or enrolled agent, they can file Form 4868 on your behalf through their professional tax software account. You do not file it yourself; you contact your tax professional, tell them you need an extension, and they submit it electronically using their credentials. They will ask you to estimate whether you owe or expect a refund, and if you owe, to estimate the amount.
Your tax professional receives the IRS confirmation and forwards it to you. This route is useful if you are already working with someone on your return or if you have a complex tax situation. There is usually no additional charge for filing an extension if you are already paying for return preparation.
What happens after you file an extension
The IRS processes your extension within a few days. You can check the status by logging into your IRS account at IRS.gov or by calling the IRS at 1-800-829-1040. The IRS will send you a confirmation letter by mail within two weeks, though the electronic confirmation you receive when you file is your proof that the extension was submitted on time.
Your new filing deadline is October 15 of the same year. You still have until then to gather documents, work with a tax professional, or prepare your return. However, if you estimated that you owe taxes when you filed the extension, you should have paid that amount by April 15. If you did not pay and you do owe when you file your return in October, you will owe interest on the unpaid balance from April 15 forward, plus a failure-to-pay penalty.
If you cannot pay what you owe
Filing an extension does not help if you cannot pay taxes you owe. The extension only gives you more time to file your return, not more time to pay. However, if you file your return and cannot pay in full, the IRS offers payment plans and other options.
When you file your return in October, you can request an installment agreement (paying in monthly installments) or an offer in compromise (settling for less than you owe, in limited circumstances). You can also request a short-term extension of the payment deadline itself, though this is separate from a filing extension. These options are available through the IRS website, by phone, or through a tax professional.
Common mistakes when filing an extension
The most common mistake is assuming an extension extends your payment deadline. It does not. If you owe taxes, you must pay by April 15 or you will owe interest and penalties, even if you file an extension and do not submit your return until October.
Another mistake is filing an extension after April 15. The extension must be filed by the original deadline to be valid. If you file after April 15, the IRS treats it as a late filing, and you may owe penalties even if you have a legitimate reason for the delay. If you realize you will miss the deadline, file the extension before midnight on April 15.
A third mistake is not keeping your confirmation. Save or print the confirmation number and the confirmation page you receive when you file. If the IRS ever questions whether you filed an extension, you will need this proof.
Frequently Asked Questions
Can I file an extension if I expect a refund?
Yes. Filing an extension does not affect your refund. If you expect a refund, you can file an extension and submit your return anytime before October 15. Your refund will be processed after the IRS receives and reviews your return, which typically takes 21 days from the date you file.
What if I file an extension but then do not file my return by October 15?
If you do not file your return by October 15, you will owe a failure-to-file penalty on top of any taxes owed. The penalty is usually 5% of the unpaid tax for each month your return is late. If you know you will miss the October deadline, contact the IRS or a tax professional before that date to discuss your options.
Do I need to file an extension if I do not owe taxes and do not expect a refund?
No. If you do not owe and do not expect a refund, you have no penalty for filing late. However, if you expect a refund, filing sooner rather than later means you receive your money sooner. An extension is useful only if you need more time to gather documents or prepare your return.
Can I file an extension on paper instead of online?
Yes. You can print Form 4868 from IRS.gov, fill it out by hand, and mail it to the IRS address listed on the form. However, mailing takes longer and you do not receive immediate confirmation. Filing online is faster and gives you proof of submission on the same day.
What if the IRS rejects my extension?
The IRS rarely rejects an extension if you file it on time and provide accurate information. If there is an issue, the IRS will send you a notice by mail explaining the problem. If you receive a rejection notice, contact the IRS at 1-800-829-1040 or work with a tax professional to file a corrected extension or to address the underlying issue.