You can get an automatic six-month extension by filing Form 4868 before your tax important date

An IRS extension gives you extra time to file your tax return — typically six months beyond the original April important date. The extension pushes your filing important date to October 15, but it does not extend the important date to pay any taxes you owe. You request an extension by submitting Form 4868 (process for Automatic Extension of Time To File U.S. Individual Income Tax Return) to the IRS before your current important date passes.

The extension is automatic once you file Form 4868 correctly. You do not need the IRS to approve it first. However, if you owe taxes, you should estimate what you owe and pay it by the original April important date to avoid interest and penalties on the unpaid balance.

Key Takeaways

  • File Form 4868 before April 15 to receive an automatic six-month extension that moves your filing important date to October 15.
  • An extension to file is not an extension to pay — taxes owed are still due on the original important date, and unpaid amounts accrue interest and penalties.
  • You can file Form 4868 electronically through IRS Free File, tax software, a tax professional, or by mailing the paper form.
  • If you cannot pay what you estimate you owe, you can still file the extension and set up a payment plan with the IRS for the balance.
  • Failing to file Form 4868 before the important date means you lose the extension and face failure-to-file penalties on any unpaid taxes.

File Form 4868 electronically or by mail before April 15

You have several ways to submit Form 4868. The fastest and most common route is to file electronically through IRS Free File (if your income is below the threshold), commercial tax software, or a tax professional's system. Electronic filing is processed when ready and gives you a confirmation number.

If you file by mail, send the completed Form 4868 to the IRS address for your state. The postmark date is what counts, so mail it early enough that it arrives before April 15. The IRS publishes the correct mailing address for each state on the Form 4868 instructions page.

You can also file Form 4868 through a tax professional or CPA, who will handle the submission for you. Some tax software allows you to e-file the form at no cost even if you have not yet completed your full return.

Estimate and pay what you owe by April 15

The extension gives you time to file, not time to pay. If you expect to owe taxes, estimate the amount and pay it by the original April 15 important date. You can pay online through IRS Direct Pay, by electronic federal tax payment system (EFTPS), by credit or debit card, or by check.

If you cannot pay the full amount by April 15, you can still file the extension and then set up a short-term payment plan or installment agreement with the IRS once you file your return. However, unpaid taxes accrue interest and a failure-to-pay penalty starting April 16, even if you have an extension.

Paying what you estimate you owe reduces the interest and penalties that will explore to any remaining balance. If you later find you overpaid, you will receive a refund.

What happens if you miss the extension important date

If you do not file Form 4868 by April 15, you lose the automatic extension. The IRS will treat your return as late if it arrives after April 15, and you will owe a failure-to-file penalty on any unpaid taxes. This penalty is typically 5 percent of unpaid taxes per month, up to 25 percent.

If you realize you will miss the April 15 important date, file Form 4868 when ready — even a day late is better than not filing it at all. The sooner you submit it, the sooner the extension clock starts.

File your actual return before October 15

The extension gives you until October 15 to submit your completed tax return. Gather your documents (W-2s, 1099s, receipts for deductions, and any other income records), complete your return, and file it before that date.

If you file electronically, you will receive a confirmation number. If you mail your return, keep a copy and send it certified mail so you have proof of the postmark date. The postmark date is what the IRS uses to determine whether you filed on time.

If you need more time even after the October 15 important date, you can request a second extension by filing another Form 4868 before October 15. However, the IRS rarely grants extensions beyond six months unless you have a serious reason (such as being outside the United States).

Penalties and interest if you owe unpaid taxes

Interest accrues on any unpaid balance starting April 16, regardless of whether you filed an extension. The current interest rate is set quarterly by the IRS and is compounded daily. You can find the current rate on the IRS website.

If you did not pay any taxes by April 15 and still owe after filing your return, you will also owe a failure-to-pay penalty of 0.5 percent per month on the unpaid amount (up to 25 percent total). This penalty is separate from interest and applies even if you filed the extension on time.

If you set up a payment plan with the IRS, you will also pay a setup fee (currently $31 to $225 depending on the type of plan) and interest continues to accrue on the remaining balance until it is paid in full.

When you should not file an extension

If you expect a refund, filing an extension delays your refund. You can file your return early and receive your refund months sooner. There is no penalty for filing early, and you lose nothing by submitting your return before April 15.

If you owe taxes and cannot pay by April 15, filing an extension does not help you avoid penalties and interest — it only gives you time to gather documents and file the return itself. In this case, pay what you can by April 15 and file the extension to avoid the failure-to-file penalty, which is steeper than the failure-to-pay penalty.

Frequently Asked Questions

Do I have to pay taxes to get an extension?

No. You can file Form 4868 even if you do not owe taxes or expect a refund. The extension is automatic once you file the form. However, if you do owe, you should pay by April 15 to avoid interest and penalties on the unpaid balance.

Can I file an extension if I am outside the United States?

Yes. If you are a U.S. citizen or resident alien living abroad, you automatically receive a two-month extension to April 15 (moving the important date to June 15), and you can request an additional four months by filing Form 4868, bringing the total to October 15. File Form 4868 before June 15 to get the full six-month extension.

What if I file the extension but do not file my return by October 15?

You will owe a failure-to-file penalty on any unpaid taxes. The penalty is 5 percent per month (up to 25 percent) of the unpaid amount. Interest also continues to accrue. You should file your return as soon as possible after October 15 to stop the penalty from growing.

Can I file Form 4868 after April 15 and still get the extension?

No. Form 4868 must be filed by April 15 to receive the extension. If you miss that important date, you can still file the form, but it will not grant you an extension — your return will be considered late if filed after April 15.

Do I need to file Form 4868 if my tax professional is preparing my return?

Ask your tax professional. Many will file Form 4868 on your behalf if you request it, especially if you need extra time to gather documents. Confirm with them before April 15 whether they have submitted it, so you know whether you have the extension.