Dec 15, 2026

What federal small-business tax payments are due on December 15, 2026?

Publication 509 (2026) says corporations deposit the fourth installment of estimated income tax for 2026 on December 15, 2026. The IRS fourth-quarter tax calendar lists that same day for partnerships to file Form 8813 and pay any tax due, and for monthly depositors to deposit Social Security, Medicare, and withheld income tax on wages paid in November.

December 15 is not the sole proprietor's estimated-tax date. Publication 509 says individual estimated-tax payments are due on the 15th day of the 4th, 6th, and 9th months of the tax year and on the 15th day of the first month after the tax year ends, which for a 2026 calendar year is January 15, 2027.

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Who it affects

Calendar-year corporations that owe a fourth installment of 2026 estimated income tax. The calendar says to see Publication 542 and EFTPS.
Partnerships that must file Form 8813, the quarterly payment voucher, and pay any tax due that day.
Employers under the monthly deposit rule, who deposit Social Security, Medicare, and withheld income tax for wages paid in November. Publication 509 also lists nonpayroll withholding for November under the monthly deposit rule on this day.
Tax-exempt organizations that must deposit fourth-quarter estimated tax on unrelated business taxable income. The calendar says to use Form 990-W to figure the amount.
Nonresident alien individuals who did not receive wages as an employee subject to U.S. income tax withholding and who timely filed Form 4868. The calendar lists Form 1040-NR for them on this day.

A sole proprietor, partner, or S corporation shareholder who pays individual estimated tax under Form 1040-ES is not on the December 15 corporate line. Use the individual rule in Publication 509, quoted in the answer above.

What to do

Match your entity to one line before you pay. A corporation's fourth 2026 installment, a partnership's Form 8813, a monthly employment-tax deposit, a tax-exempt organization's unrelated-business estimated tax, and an individual Form 1040-ES payment are different obligations.
If you are a calendar-year corporation, deposit the fourth installment of 2026 estimated income tax on December 15, 2026. Publication 509 states that date. The IRS calendar points corporations to Publication 542 and EFTPS for the deposit.
If the monthly deposit rule applies, deposit November's Social Security, Medicare, and withheld income tax on December 15, 2026. Semiweekly depositors follow the semiweekly dates on the same calendar, not this monthly date.
Schedule an EFTPS payment by 8 p.m. Eastern Time at least one calendar day before December 15. The IRS fourth-quarter tax calendar states that rule, so the scheduling cutoff for a December 15 payment is December 14.
Do not move a sole proprietor's last 2026 estimated-tax payment up to December 15. Under the Publication 509 rule quoted above, that installment falls on January 15, 2027. January 15, 2027 is a Friday, so the weekend rule does not move it.

Verified dates

December 15, 2026
Corporations: deposit the fourth installment of 2026 estimated income tax.
Source: IRS: Publication 509 (2026) · IRS: Fourth quarter tax calendar
December 15, 2026
Partnerships: file Form 8813 and pay any tax due. Monthly depositors: deposit November employment taxes. Tax-exempt organizations: deposit fourth-quarter estimated tax on unrelated business taxable income.
Source: IRS: Fourth quarter tax calendar
January 15, 2027
For a calendar-year individual, the Publication 509 estimated-tax rule puts the installment that follows the tax year on this day. This is outside the next-60-day window that starts October 30, 2026. It is listed so it is not confused with December 15.
Source: IRS: Publication 509 (2026), estimated tax payments rule

FAQ

Is December 15, 2026 the estimated-tax deadline for a sole proprietor or single-member LLC?

Not under the individual rule. Publication 509 says individual estimated-tax payments are due on the 15th day of the 4th, 6th, and 9th months of the tax year and on the 15th day of the first month after the tax year ends. For a calendar-year individual, that last 2026 installment is January 15, 2027. December 15, 2026 is the date Publication 509 gives corporations for the fourth installment of 2026 estimated income tax. A single-member LLC taxed as a sole proprietor follows the individual rule. A corporation, including an LLC taxed as a corporation, follows the corporate line.

What is the Form 8813 payment on December 15, 2026?

The IRS fourth-quarter tax calendar lists December 15, 2026 for partnerships to file Form 8813, the quarterly payment voucher, and pay any tax due. This page does not restate who must withhold or how much is due. Read the Form 8813 instructions for the partnership's facts.

Do all employers deposit November payroll taxes on December 15, 2026?

No. The IRS calendar limits that December 15, 2026 deposit to employers under the monthly deposit rule, for Social Security, Medicare, and withheld income tax on payments made in November. Publication 509 states the same monthly-deposit line, and a separate nonpayroll-withholding line for monthly depositors. Semiweekly depositors use the semiweekly dates listed on the same calendar.

What else does the IRS put on December 15, 2026?

Besides the corporate estimate, Form 8813, and the monthly employment-tax deposit, the fourth-quarter tax calendar lists two more lines. Nonresident alien individuals who did not receive wages as an employee subject to U.S. income tax withholding file Form 1040-NR if they timely filed Form 4868. Tax-exempt organizations deposit fourth-quarter estimated tax on unrelated business taxable income and use Form 990-W to figure the amount.

When do I have to schedule the December 15 payment in EFTPS?

The IRS fourth-quarter tax calendar says EFTPS users must schedule payments by 8 p.m. Eastern Time at least one calendar day before the tax due date. For a payment due December 15, 2026, that scheduling cutoff is December 14, 2026.

Free tool

The free Deadline Finder filters dated changes by the tools a business uses. Pair this December 15 page with the November 2 Form 941 page if you have employees. The free FIRE to IRIS check is for 1099 e-file headers, not for estimated-tax payments.

Sources

IRS: Publication 509 (2026), Tax Calendars (December 15 corporate estimated tax; the individual estimated-tax timing rule; the monthly deposit rule for November wages). IRS: Fourth quarter tax calendar (December 15, 2026 lines for corporations, partnerships and Form 8813, monthly employment-tax deposits, Form 1040-NR, and tax-exempt organizations, plus the EFTPS scheduling note).

Checked October 30, 2026. Re-check the official page before you act. A disaster relief notice can move a federal tax date for a named area.

Copy-paste prompt for any AI agent

I run a small U.S. business. Please help me check what, if anything, is due on December 15, 2026. Use only Publication 509 (2026) and the IRS fourth-quarter tax calendar.
1. Quote the Publication 509 line for corporations on December 15.
2. Quote the individual estimated-tax timing rule and say what date it produces for a calendar-year 2026 individual. Do not call that date December 15.
3. Quote the calendar lines for Form 8813, monthly employment-tax deposits, Form 1040-NR, and tax-exempt organization estimated tax.
4. Tell me which of those lines can apply only after I tell you our entity type and whether we are a monthly or semiweekly depositor. If I have not said, list the questions instead of guessing.
5. Quote the EFTPS scheduling rule.
Do not calculate a payment, do not file anything, and do not log in to any account. When you state a date, quote the exact line. If you cannot find that line, say "no deadline line found" instead of guessing.

Not advice

General guidance, not legal, tax, or IT advice. Which December 15 line applies depends on entity type, elections, and deposit schedule. Check the IRS pages linked above or ask a tax professional for your case. Not affiliated with or endorsed by the IRS.

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