How to File a Form 8804 Extension Using Form 7004

A partnership that owes Section 1446 withholding tax gets more time to file Form 8804 by submitting Form 7004 on or before the original due date. The Form 8804 extension is automatic and runs six months, so a calendar-year domestic partnership moves from March 15 to September 15. It extends the paperwork only. The full tax is still due on the original date, and any shortfall paid after that starts running penalties and interest.

How to File Form 7004 for Form 8804

Form 7004 is the only form you need. You don’t have to explain why you want more time; if the form arrives at the IRS by the original due date and is filled in correctly, the six-month extension is granted.¹

In Part I, enter Form Code 31. That code tells the IRS the extension is for Form 8804 specifically.² Part II takes the partnership’s legal name, address, and EIN.

Form 8804 is treated separately from Form 1065. Extending one does not extend the other, so you file a separate Form 7004 for each return.³

Three lines drive the money side:

Line 6: your best estimate of the partnership’s total Section 1446 tax for the year.
Line 7: payments and credits already made, including installments paid during the year on Form 8813.
Line 8: the balance due, which is Line 6 minus Line 7. Anything on Line 8 has to be paid when you submit the extension.²

The IRS accepts Form 7004 electronically through Modernized e-File, and that is the fastest route.⁴ Paper is accepted; the mailing address is in the Form 7004 instructions.

Original and Extended Due Dates

The original deadline depends on the partnership:

Most domestic partnerships on a calendar year: March 15, the 15th day of the third month after the tax year closes. A six-month extension moves the filing date to September 15.⁵
Partnerships keeping their books outside the U.S. and Puerto Rico, or made up entirely of nonresident alien partners: June 15. With a six-month extension, the filing date becomes December 15.³

Weekend and holiday dates shift to the next business day. For tax year 2025, March 15, 2026 falls on a Sunday, so the original due date is Monday, March 16, 2026.³

The Extension Does Not Postpone Payment

This is where partnerships get burned. Form 7004 moves the return deadline, not the payment. The entire Section 1446 liability is still due on the original date, and any amount not already covered by installments has to travel with the extension.

During the year, partnerships pay Section 1446 tax in quarterly installments on Form 8813, due on the 15th day of the 4th, 6th, 9th, and 12th months of the tax year.⁶ For a calendar-year partnership, that means April 15, June 15, September 15, and December 15. Those payments go on Line 7 of Form 7004 so the IRS can see whether a balance remains.

If the installments fell short, pay the difference with the extension. If they overshot, the partnership gets a credit or refund once the IRS processes the final Form 8804. Electronic payments run through EFTPS, and new enrollments there can take up to five business days to activate, so a partnership setting it up for the first time needs to start early.⁷

Form 8805 Follows the Extended Date

Alongside Form 8804, the partnership prepares a Form 8805 for each foreign partner showing that partner’s share of the Section 1446 tax withheld. Each partner must receive their Form 8805 by the due date of the partnership return, including extensions.³ A valid extension to September 15 pulls the Form 8805 distribution date to September 15 as well.

Foreign partners rely on Form 8805 to claim credit on their own U.S. returns for the tax withheld on their behalf. Late or inaccurate Forms 8805 carry their own penalties, separate from anything imposed on Form 8804.

Penalties and Interest If You Miss

Two penalties can run at the same time:

Failure to file: 5% of the unpaid tax per month or part of a month, capped at 25%. This applies when Form 8804 is late and no extension was requested, or when the return misses the extended date.⁸
Failure to pay: 0.5% of the unpaid tax per month, also capped at 25%. This one applies whenever the tax isn’t paid by the original due date, even if a valid extension was filed.⁸

When both apply in the same month, the failure-to-file penalty is reduced by the failure-to-pay penalty for that month. After five months both stacked, the failure-to-file portion tops out; failure-to-pay keeps running.

Interest compounds daily on unpaid tax from the original due date until it’s paid. The IRS resets the underpayment rate quarterly at the federal short-term rate plus three percentage points. For the quarter beginning April 1, 2026, the underpayment rate is 6%.⁹ Interest keeps running even when a penalty is waived; the IRS rarely abates interest on its own.

An accuracy-related penalty of 20% of the underpayment can attach if the tax reported on Form 8804 is substantially understated.¹⁰ A substantial understatement generally means the shortfall exceeds the greater of 10% of the correct tax or $5,000. That is a strong reason to get the Line 6 estimate close to right before the original deadline, not just close enough.

Asking for Penalty Relief

Both failure-to-file and failure-to-pay penalties can be abated for reasonable cause. The Form 8804 instructions are specific about how to raise it: don’t attach an explanation to the return. Wait for the penalty notice, then respond to it with your reasoning, and the IRS will evaluate against its reasonable-cause criteria.¹¹

Reasonable cause means the partnership used ordinary business care and still could not comply because something outside its control got in the way. A separate waiver process covers penalties tied to late or incorrect Forms 8805.¹¹ Forgetting the deadline or not knowing about it won’t clear the bar. Reliance on a tax professional who failed to file, a natural disaster, or records stuck in a foreign jurisdiction can.

1
eCFR. 26 CFR 1.6081-2 – Automatic Extension of Time to File Certain Returns
2
Internal Revenue Service. Form 7004 – Application for Automatic Extension of Time To File Certain Business Income Tax, Information, and Other Returns
3
Internal Revenue Service. Instructions for Forms 8804, 8805, and 8813
4
Internal Revenue Service. E-Filing Form 7004
5
Internal Revenue Service. Reporting and Paying Tax on Partnership Withholding
6
eCFR. 26 CFR 1.1446-3 – Time and Manner of Calculating and Paying Over the 1446 Tax
7
Internal Revenue Service. EFTPS: The Electronic Federal Tax Payment System
8
Internal Revenue Service. Failure to File Penalty
9
Internal Revenue Service. Internal Revenue Bulletin: 2026-8
10
Office of the Law Revision Counsel. 26 USC 6662 – Imposition of Accuracy-Related Penalty on Underpayments
11
Internal Revenue Service. Instructions for Forms 8804, 8805, and 8813