Two dates drive the business tax deadlines 2027 for most calendar-year LLCs and corporations. Partnerships (including multi-member LLCs taxed by default as partnerships) and S corporations file by March 15, 2027. Sole proprietors, single-member LLCs filing a Schedule C, and C corporations file by April 15, 2027.
The last 2026 estimated tax payments are due December 15, 2026 for corporations and January 15, 2027 for individuals. This guide covers those dates, the extension rules, the payroll dates that come first, and a calendar you can copy. Dates are current as of November 8, 2026.
Key Takeaways
- Your tax classification, not your state filing, sets your federal deadline.
- March 15, 2027: Form 1065 and Form 1120-S. April 15, 2027: Form 1040 with Schedule C and Form 1120.
- An extension gives you more time to file, not more time to pay.
- Payroll and 1099 filings land on February 1, 2027, before the income tax returns.
- State annual reports and franchise taxes run on their own calendar.
First, Figure Out How Your Entity Is Taxed
Your state filing doesn’t decide your federal deadline. Your tax classification does. According to the IRS, an LLC with one owner is by default a “disregarded entity” reported on the owner’s Form 1040. An LLC with two or more owners is by default taxed as a partnership. Either kind can elect to be taxed as a corporation.
Not sure which one you are? Our guide to single-member LLC taxes and the S corporation election walks through it.
| How you’re taxed | Federal form | Calendar-year due date for 2026 returns |
|---|---|---|
| Sole proprietor / single-member LLC (default) | Form 1040 with Schedule C | April 15, 2027 |
| Multi-member LLC (default) or partnership | Form 1065 (plus Schedules K-1) | March 15, 2027 |
| S corporation (including an LLC that elected S status) | Form 1120-S (plus Schedules K-1) | March 15, 2027 |
| C corporation (including an LLC that elected C status) | Form 1120 | April 15, 2027 |
The pattern follows an IRS rule, and IRS Publication 509 lists the tax calendars. Partnerships and S corporations file by the 15th day of the third month after year-end. C corporations file by the 15th day of the fourth month.
Using a fiscal year instead of the calendar year? Your dates shift, and special rules apply, including for some C corporations with a June 30 year-end. If that’s you, check the form instructions before you plan.
Business Tax Deadlines 2027: Extensions Give You Time to File, Not Pay
According to the IRS, an extension gives you extra time to file. It doesn’t give you extra time to pay. Interest and late-payment penalties can still apply to any unpaid balance after the original due date.
| Entity | Extension form | Extended deadline (calendar year) |
|---|---|---|
| Partnership / multi-member LLC | Form 7004 | September 15, 2027 |
| S corporation | Form 7004 | September 15, 2027 |
| C corporation | Form 7004 | October 15, 2027 |
| Sole proprietor / single-member LLC | Form 4868 (individual extension) | October 15, 2027 |
Each of these extensions runs six months, according to the IRS instructions for Form 7004 and Form 4868.
Here’s the part people always miss: single-member LLC owners often reach for Form 7004 by mistake. If your LLC hasn’t elected corporate tax treatment, its income goes on your personal return. The individual extension, Form 4868, is the one that applies.
Penalties for Missing the March 15 Date
The IRS charges partnerships and S corporations a late-filing penalty per partner or shareholder, per month, for a limited number of months. The dollar amount is adjusted for inflation each year, so check the Form 1065 and Form 1120-S instructions for the 2027 figure.
Because the penalty grows with the number of owners, filing the extension request on time is cheap insurance.
For individual returns, the IRS explains in Topic No. 653 that the failure-to-file penalty is generally larger than the failure-to-pay penalty. So file on time, or extend, even if you can’t pay in full.
Estimated Tax Payments for 2026 and 2027
If nobody withholds tax from your business income, the IRS expects you to pay during the year. The schedule differs for individuals and corporations.
Individuals: Sole Proprietors, Single-Member LLC Owners, Partners, and S Corp Shareholders
According to the IRS (Form 1040-ES instructions), estimated payments for a calendar year are generally due April 15, June 15, September 15, and January 15 of the following year.
| Payment | 2026 tax year | 2027 tax year |
|---|---|---|
| 1st | April 15, 2026 (past) | April 15, 2027 |
| 2nd | June 15, 2026 (past) | June 15, 2027 |
| 3rd | September 15, 2026 (past) | September 15, 2027 |
| 4th | January 15, 2027 | January 2028 (check the IRS for the exact day, since the 15th falls on a weekend and a holiday follows) |
The IRS generally lets you avoid the underpayment penalty if you owe less than $1,000 after withholding and credits, or if you pay at least 90% of this year’s tax or 100% of last year’s, whichever is smaller. Special rules apply to certain higher-income taxpayers. Say your tax bill will be $12,000. Four payments of $3,000 each keep you on track.
C Corporations
According to IRS Publication 542, calendar-year corporations generally pay estimated tax in installments due on the 15th day of the 4th, 6th, 9th, and 12th months. For 2026, that means April 15, June 15, September 15, and December 15, 2026. Special rules apply to large corporations, and a corporation generally has to make these payments only if it expects to owe $500 or more.
S Corporations and Partnerships
These entities generally don’t pay federal income tax at the entity level. The owners pay estimated tax on their share of the income.
If you’re an S corp shareholder-employee, you may be able to cover some of that tax through payroll withholding on your own wages instead.
Business Tax Deadlines 2027 Before March 15: Payroll and 1099s
If you have employees or pay contractors, the first big deadline arrives about six weeks before the income tax returns.
| Item | 2027 due date |
|---|---|
| W-2s to employees and to the Social Security Administration (with Form W-3) | February 1, 2027 |
| Form 1099-NEC to contractors and to the IRS | February 1, 2027 |
| Form 941 (fourth-quarter payroll tax return) | February 1, 2027 (the IRS allows later filing if all deposits were made on time) |
| Form 940 (annual federal unemployment tax) | February 1, 2027 (February 10, 2027 if you deposited all FUTA tax on time) |
According to the IRS, when a due date falls on a Saturday, Sunday, or legal holiday, the deadline moves to the next business day. January 31, 2027 is a Sunday, so the W-2/W-3, Form 1099-NEC, and Form 940 deadlines roll to Monday, February 1. Employers who deposited all FUTA tax on time get 10 extra days to file Form 940, until February 10.
Confirm each form’s date in the IRS instructions for that form.
Don’t Miss the S Election Deadline
Want your LLC or corporation taxed as an S corporation starting January 1, 2027? The IRS says Form 2553 generally must be filed no more than two months and 15 days after the start of the tax year the election takes effect. For a calendar-year election, that’s March 15, 2027.
If you miss it, late-election relief may be available under Rev. Proc. 2013-30. You’ll need an EIN to file, and our guide on how to get an EIN for your LLC for free shows how.
State Deadlines Are Separate
Federal dates are only part of the picture. Your state may also require an annual report, franchise tax, or a state income or LLC tax return, often on different dates.
Here are a few examples. Confirm any figure with the state agency before you rely on it.
- Delaware: According to the Delaware Division of Corporations, LLCs owe a $400 annual tax due June 1, and corporations have franchise tax and annual reports due March 1. See our Delaware LLC guide for more.
- California: According to the Franchise Tax Board, every LLC doing business or organized in California must pay an $800 annual tax.
- Texas: Franchise tax has its own thresholds. See our guide to Texas franchise tax for LLCs.
- Your state: Use our LLC annual report fees and deadlines by state page to find your due date and fee, then add them to your calendar.
Missing a state filing can mean penalties. Ignore it long enough and you can face administrative dissolution and lose good standing. The timeline varies by state.
Does Beneficial Ownership (BOI) Reporting Belong on Your Calendar?
Many readers ask about the Corporate Transparency Act. No, if your company was formed in the U.S. According to FinCEN, a final rule issued August 11, 2026 exempts U.S. companies from beneficial ownership reporting. Foreign entities registered to do business in a U.S. state may still have to report. Our BOI explainer has the details.
Business Tax Deadlines 2027 Calendar You Can Copy
Set reminders two to three weeks before each date.
- November–December 2026: Review year-to-date profit. C corporations make the December 15 estimated payment. Confirm payroll and contractor details (names, addresses, taxpayer IDs, W-9s).
- January 15, 2027: Make the individual estimated payment. Finish W-2s and 1099-NECs.
- February 1, 2027: File W-2s, 1099-NECs, and fourth-quarter payroll returns.
- March 15, 2027: File Form 1065 or 1120-S (or Form 7004), issue K-1s, and file Form 2553 if you’re electing S status for 2027.
- April 15, 2027: File Form 1040 with Schedule C or Form 1120 (or an extension), pay any balance due, and make the first 2027 estimated payment.
- June 15 and September 15, 2027: Make estimated payments. Extended partnership and S corp returns are due September 15.
- October 15, 2027: Extended C corp and individual returns are due.
- Your state’s annual report date: Add it from the state-by-state page above.
Where Bookkeeping Fits
Every date above depends on clean books. Reconciled bank statements, categorized expenses, and a profit-and-loss report let you calculate estimated payments and prepare returns without a scramble.
Separate accounts help too. Commingled funds are a common argument for piercing the corporate veil, and the standards vary by state. If you don’t have a dedicated account yet, see what to compare before you apply for a business bank account.
You can do monthly bookkeeping yourself with a spreadsheet or basic accounting software. Paid help tends to be worth it when you have payroll, multiple owners, inventory, or books that are months behind. A tax professional is worth consulting on S election timing and on the choice between extending and filing on time.
FAQ
Is the 2026 tax return due in 2026 or 2027?
The 2026 tax year ends December 31, 2026, and returns are filed in 2027. For calendar-year businesses, that’s March 15, 2027 (partnerships and S corporations) or April 15, 2027 (sole proprietors, single-member LLCs, and C corporations).
Does a single-member LLC file its own federal tax return?
Not by default. According to the IRS, a single-member LLC that hasn’t elected corporate treatment reports its income and expenses on the owner’s Form 1040 (usually Schedule C). The April 15 individual deadline applies.
If I file an extension, do I still have to pay by the original date?
Generally, yes. An extension gives you more time to file. The IRS still expects payment of tax owed by the original due date, and interest and penalties can apply to unpaid amounts.
Do I still owe state annual reports if my business earned no income?
Usually yes. State annual reports and franchise or LLC taxes are typically based on your entity’s registration, not its profit. Check your state’s Secretary of State or tax agency for the rule and fee.
What happens if I miss a deadline?
Federal penalties and interest can start accruing, and a missed state filing can eventually affect your good standing. File as soon as you can. Ask the IRS or your state agency about penalty relief if you have a reasonable explanation.
Your Next Step
Open the LLC annual report fees and deadlines by state page, find your state, and add its due date to the calendar above today. Do it before the December 15 and January 15 payments arrive.
Last updated: November 8, 2026
Disclaimer: The information in this article is for educational purposes only and does not constitute legal, tax, or financial advice. Business formation rules, fees, and deadlines vary by state and change often. Always consult a qualified attorney, CPA, or tax professional before making decisions about your business.
