When Is Form 1042 Due? Extensions, Penalties, and Filing

Form 1042 is due on March 15 of the year following the calendar year in which the U.S.-source income was paid to foreign persons. When March 15 falls on a Saturday, Sunday, or legal holiday in the District of Columbia, the due date moves to the next business day. For tax year 2025, that pushes the deadline to March 16, 2026, because March 15, 2026, is a Sunday.¹

The rule comes from Treasury Regulations, which set the deadline as the 15th day of the third month after the calendar year ends. For any withholding agent on a calendar year, that always lands on March 15.² Form 1042-S, which reports the amounts paid to each individual foreign recipient, shares the same date. Both the IRS copy and the recipient copy of Form 1042-S must go out by March 15 as well.³ Filing one on time and the other late still exposes you to penalties on the late form.

Getting More Time to File

Form 1042 and Form 1042-S use different extension forms. Confusing them is a common and costly error.

Extending Form 1042 with Form 7004

File Form 7004 on or before March 15 to receive an automatic six-month extension, which moves your filing deadline to September 15.⁴

The extension covers the paperwork only. Any tax owed is still due on March 15, and interest starts running on any unpaid balance from that date regardless of the extension.⁴

Extending Form 1042-S with Form 8809

Form 7004 does not extend Form 1042-S. To buy time on the information returns, file Form 8809. An approved Form 8809 gives you an automatic 30-day extension and can be submitted electronically.⁵

Deposits Are Due Long Before March 15

The tax itself is not paid on the filing date. Deposits run on a rolling calendar throughout the year, and the frequency depends on how much undeposited tax has piled up.⁶

$2,000 or more at the end of a quarter-monthly period (the 7th, 15th, 22nd, and last day of each month): deposit within 3 business days.
$200 to $1,999 at the end of a month: deposit within 15 days after the month ends.
Less than $200 at the end of the calendar year: deposit the balance or remit it with Form 1042 by March 15.

All deposits must go through the Electronic Federal Tax Payment System (EFTPS) or IRS Direct Pay. Mailing a check to the IRS for a deposit triggers a 10% penalty on the amount involved, whether or not the payment arrives on time.¹ Setting up EFTPS access and, where required, obtaining a Transmitter Control Code well before your first deposit is due matters more than the paper deadlines suggest.⁷

What It Costs to Miss the Date

The IRS treats a late return and unpaid tax as separate violations. Penalties stack when both apply.

Failure to File

If you miss the deadline (including any valid extension), the penalty is 5% of the unpaid tax for each month or partial month the return is late, capped at 25%.⁸ For a withholding agent sitting on $500,000 in unpaid tax, that is up to $25,000 per month until the return is filed.

Failure to Pay

Unpaid tax carries a separate 0.5% monthly penalty, also capped at 25%. When both penalties apply in the same month, the failure-to-file penalty is reduced by the failure-to-pay amount, so the combined bite is 5% rather than 5.5%.⁹ If the IRS issues a notice of intent to levy and you still do not pay within 10 days, the monthly rate rises to 1%.⁷

Interest

Interest compounds daily on any unpaid balance from the original due date. The rate resets each quarter at the federal short-term rate plus three percentage points. For the first quarter of 2026, the underpayment rate is 7%; for the second quarter of 2026, it drops to 6%.¹⁰ Large corporate underpayments over $100,000 face the short-term rate plus five percentage points.¹¹ Interest also runs on penalties.

Asking for Penalty Relief

If circumstances outside your control caused the late filing or payment, the IRS may waive penalties under its reasonable-cause standard. This is a case-by-case determination and the burden of proof is on you.

Circumstances the IRS recognizes include natural disasters, serious illness or death of the taxpayer or an immediate family member, inability to access records, and system failures that blocked timely electronic filing. Simply not knowing about the deadline, relying on a tax professional who failed to deliver, or lacking available funds generally do not qualify.¹²

For information-return penalties (late Forms 1042-S in particular), you also have to show you acted responsibly both before and after the failure: requesting extensions when possible, correcting the problem quickly, and pointing to mitigating factors like a first-time filing of the form or a strong compliance history.¹²

How to File by the Deadline

Paper Filing

If you qualify to file on paper, mail Form 1042 to:

Internal Revenue Service
P.O. Box 409101
Ogden, UT 84409

There is no separate payment address, because deposits must go through EFTPS or IRS Direct Pay. A year-end balance under $200 can be remitted with the return, but the payment itself still has to move through one of those electronic systems to avoid the 10% deposit penalty.¹

Electronic Filing

Withholding agents filing 10 or more information returns in aggregate (counting all return types, including W-2s) must file electronically.¹³ Most agents issuing Form 1042-S clear that threshold without difficulty.

The intake system is changing. The IRS has used FIRE for information returns for years, and IRIS (the Information Returns Intake System) is replacing it. The IRS is targeting tax year 2026 (filing season 2027) as the date FIRE is fully retired and IRIS becomes the sole intake system. Current FIRE Transmitter Control Code holders are advised to complete an IRIS application now rather than wait for the cutoff.¹³ TCC applications can take up to 45 business days to process, which is worth building into any timeline aimed at a March 15 filing.

1
Internal Revenue Service. Instructions for Form 1042 (2025)
2
eCFR. 26 CFR 1.1461-1 – Payment and Returns of Tax Withheld
3
Internal Revenue Service. Instructions for Form 1042-S (2026)
4
Internal Revenue Service. Instructions for Form 7004 (Rev. December 2025)
5
Internal Revenue Service. About Form 8809, Application for Extension of Time to File Information Returns
6
Internal Revenue Service. 2025 Instructions for Form 1042
7
Internal Revenue Service. Notice 746 – Information About Your Notice, Penalty and Interest
8
Office of the Law Revision Counsel. 26 USC 6651 – Failure to File Tax Return or to Pay Tax
9
Internal Revenue Service. Failure to Pay Penalty
10
Internal Revenue Service. Internal Revenue Bulletin 2026-08
11
Internal Revenue Service. Quarterly Interest Rates
12
Internal Revenue Service. Penalty Relief for Reasonable Cause
13
Internal Revenue Service. Filing Information Returns Electronically (FIRE)