Mail your Form 4868 and payment to the IRS service center that handles returns for your state

The address depends on where you live and whether you are including a payment with your form. The IRS publishes a specific mailing address for Form 4868 (Application for Automatic Extension of Time To File U.S. Individual Income Tax Return) in the form's instructions each year, and that address changes based on your state and whether you are paying tax owed.

You do not mail Form 4868 to the same address as your regular tax return. The IRS routes extension requests to a separate processing center. Using the wrong address delays your extension and may result in the form not being recorded in time.

The safest approach is to check the current Form 4868 instructions on IRS.gov before you mail anything. The instructions include a table that lists the correct mailing address for each state. Print those instructions or bookmark that page so you have the exact address.

Key Takeaways

  • Form 4868 has a different mailing address than your regular tax return, and the address varies by state.
  • The IRS publishes the correct mailing address in the Form 4868 instructions each year on IRS.gov.
  • If you are paying tax with your form, use the address listed for payments in the instructions, not the address for returns without payment.
  • Mail your form at least one week before the tax deadline to allow time for delivery and processing.
  • Keep a copy of Form 4868 and your payment receipt or cancelled check for your records.

How to find the correct mailing address for your state

Go to IRS.gov and search for "Form 4868 instructions." Download the PDF for the current tax year. Open the instructions and look for the section titled "Where to File" or "Mailing Address." This section contains a table organized by state.

Find your state in the table. The table will show you one address if you are mailing the form without payment, and a different address if you are including a check or money order. Use the address that matches your situation. Some states have multiple addresses depending on the county you live in, so read the table carefully.

Write the address exactly as shown in the instructions. The IRS uses optical scanning to sort mail, and an incorrect address format can cause delays. Do not abbreviate state names or use a different format than what appears in the instructions.

Mailing Form 4868 with a payment

If you are sending a check or money order with your Form 4868, use the payment address listed in the instructions, not the address for forms without payment. The payment address routes your form and check to a lockbox facility that processes payments separately from extension requests.

Write your check or money order payable to "United States Treasury." Write your Social Security number, the tax year (for example, "2024"), and "Form 4868" on the front of the check. Do not send cash.

Include a copy of your completed Form 4868 with the check. Do not staple the check to the form. Place both in the same envelope. The lockbox will separate them during processing, but they need to arrive together so the payment gets matched to your extension request.

Timing: when to mail your form

Mail your Form 4868 at least one week before the tax deadline. The standard tax deadline is April 15, so mail your form by April 8 to allow time for delivery. If April 15 falls on a weekend or holiday, the deadline moves to the next business day — check IRS.gov that year to confirm the exact date.

The IRS considers Form 4868 filed on the date it is postmarked, not the date it arrives. Use first-class mail or a service that provides a postmark. If you mail the form on April 14 and it is postmarked April 14, the IRS will treat it as timely even if it does not arrive until April 20.

If you are mailing a payment with your form, the postmark date also controls whether the payment is considered on time. A payment postmarked by the deadline is on time for extension purposes, even if it arrives late. However, interest and penalties begin accruing on any unpaid tax from the original deadline, so paying early reduces the interest you owe.

What to keep for your records

Make a photocopy of your completed Form 4868 before you mail it. Keep that copy with your tax records for the year. If the IRS ever questions whether you filed for an extension, you will have proof of what you submitted.

If you are paying by check, write down the check number and the amount. Keep that information with your copy of the form. If you are paying by money order, keep the receipt or a photo of the money order stub.

The IRS will not send you a confirmation that your extension was received. You will not get a letter or email saying "your Form 4868 was processed." The only way to verify that your extension was recorded is to file your actual tax return later and check whether the IRS accepted it without penalty for late filing.

If you do not receive a confirmation

The IRS does not issue receipts or confirmations for Form 4868. This is normal. Your extension is either recorded or it is not, and you will find out when you file your return.

If you are concerned that your form did not arrive, you can call the IRS at 1-800-829-1040 and ask whether an extension is on file for your Social Security number. Have your Social Security number and the tax year ready. The IRS can tell you whether they have a record of your extension request.

If the IRS has no record of your extension and your original deadline has passed, you may owe a failure-to-file penalty. If this happens, file your return as soon as possible and include a statement explaining that you mailed Form 4868 on time. The IRS may waive the penalty if you can show that you made a good-faith effort to file for an extension.

Frequently Asked Questions

Can I email or fax Form 4868 instead of mailing it?

No. The IRS only accepts Form 4868 by mail or through electronic filing. If you file taxes electronically through tax software or a tax professional, you can request an extension electronically without mailing anything. If you are mailing a paper return, you must mail the form itself.

What if I mail my Form 4868 to the wrong address?

The form may not be processed in time, and your extension may not be recorded. If you realize you used the wrong address, call the IRS at 1-800-829-1040 immediately and explain what happened. They may be able to help, but the safest approach is to mail a second copy to the correct address right away.

Do I need to include a payment with Form 4868?

No. You can file Form 4868 without paying anything. The form itself gives you six months to file your return. If you owe tax, you can pay it when you file your return later. However, interest and penalties on unpaid tax begin accruing from the original deadline, so paying early reduces what you owe.

What happens if my check is lost in the mail?

If your check does not arrive, the IRS will not have a record of the payment. When you file your return, the IRS will show that you owe the original amount plus interest and penalties. If you can prove the check was mailed (by showing a cancelled check or money order receipt), you can contact the IRS and ask them to credit the payment. Keep copies of everything for this reason.

Can I mail Form 4868 after the tax deadline has passed?

No. Form 4868 must be postmarked by the tax deadline to be valid. If you miss the deadline, you cannot file for an extension retroactively. File your return as soon as possible and include a statement explaining why you are late. The IRS may reduce or waive penalties if you have a reasonable cause.