Form 4868: how to fill it out, file it and pay with it

What is Form 4868 and who uses it?

Form 4868 is the one-page IRS request for an automatic extension of time to file an individual income tax return. It covers Forms 1040, 1040-SR, 1040-NR and 1040-SS, and it grants six more months, or four more for U.S. citizens and residents who are out of the country and already have two (Form 4868 instructions).

To qualify, the instructions list three conditions: properly estimate your tax liability with the information you have, enter that total on line 4, and file the form by the return's due date. For tax year 2026 that due date is Thursday, April 15, 2027.

You do not give a reason. The IRS contacts you only if it denies the request. Do not use Form 4868 if you want the IRS to figure your tax, or if a court order requires you to file by the regular due date.

Form 4868 instructions, line by line

The form has two parts. Part I identifies you and Part II is a four-line tax estimate, plus two checkboxes for special cases. Here is what goes on each line.

How to estimate your tax and payment for Form 4868

A reasonable estimate uses the documents you have by April. Start from last year's return, then adjust for what changed. The goal is a number close enough that you pay most of what you owe, not a finished return.

1. Collect W-2s, 1099s, and any partial records for income you are still waiting on.
2. Rough out taxable income and tax using your software's draft return or last year's figures scaled up or down.
3. Add self-employment tax and other taxes you expect, to reach the line 4 total.
4. Add up federal withholding from W-2s and 1099s, plus your 2026 estimated tax payments, for line 5.
5. Subtract to get line 6, then decide how much you can pay on line 7.

Worked example

A freelancer expects $18,500 of total tax for 2026 (line 4). She had $2,400 withheld from a part-time W-2 job and made $12,000 in quarterly estimated payments, so line 5 is $14,400 and line 6 is $4,100. She pays $4,100 by April 15, 2027. If her final return shows $18,900, only $400 is paid late, and the failure-to-pay penalty is waived for the extension period because she paid at least 90% of her tax by April 15 and will pay the rest with the return.

That 90% rule comes from the Form 4868 instructions: you are treated as having reasonable cause for late payment during the extension if at least 90% of your total tax is paid by the original due date through withholding, estimated payments or payments with Form 4868, and the remainder is paid with the return. Interest still runs on the $400.

Can I file Form 4868 online?

Yes. You can e-file Form 4868 through tax software, through a tax professional who uses IRS e-file, or free through IRS Free File, which has no income limit for extension requests (IRS). The software will ask for figures from your prior-year return to verify your identity.

After you submit, you receive an electronic acknowledgment. Keep it with your tax records. Do not mail a paper copy of an e-filed Form 4868 unless you are sending a check or money order with it.

Extension by payment instead of the form

If you pay part or all of your estimated balance electronically and mark the payment as an extension, you do not need to file Form 4868 at all. The IRS processes the extension automatically. Eligible methods include IRS Direct Pay, your IRS online account, EFTPS, and debit card, credit card or digital wallet payments through the IRS's approved processors; our IRS Direct Pay guide explains how that free bank-account option works.

Save the confirmation number the payment system gives you. It is your record that the extension payment was made on time, and it helps if a later notice shows the payment missing.

Form 4868 mailing address

If you file on paper, the address depends on your state and on whether you enclose a payment. These are the addresses printed on the 2025 Form 4868; confirm them on the 2026 form before mailing in 2027.

Mail it by April 15, 2027. A postmark on or before the due date counts as timely. Private delivery services cannot deliver to P.O. boxes, so a check-enclosed form sent by courier needs the street address the IRS lists for private delivery services.

Fiscal-year taxpayers must file a paper Form 4868; e-filing is not available to them.

Do I need to pay with Form 4868?

No payment is required to get the extension, but the form does not extend the time to pay. Tax not paid by April 15, 2027 accrues interest, and usually the failure-to-pay penalty of 0.5% per month, until paid (IRS, Failure to pay penalty). Our page on getting an extension to pay taxes covers the options if you cannot send the full amount.

When you file the return, claim what you paid with the extension on Schedule 3, line 10 (on the 2025 form layout). If spouses each filed a separate Form 4868 but then file jointly, add both payments together on the joint return.

What happens after you file Form 4868?

In most cases, nothing visible happens. The extension is automatic, and the IRS only writes if it denies the request. Your job is to file the complete return by Friday, October 15, 2027.

• Do not attach Form 4868 to your return; just report any payment made with it.
• You can file any time before October 15; filing early stops interest sooner if you still owe.
• If you get a balance-due notice such as CP14 after filing, the extension payment may not have been credited; compare the notice to your confirmation number. See IRS notice CP14.
• If you missed April 15 without an extension, Form 4868 can no longer be used; file the return as soon as you can and read tax extension penalty for what it will cost.

For the bigger picture, including the three methods side by side, return to the tax extension guide. All the 2027 dates are on the tax extension deadline 2027 page.