Most small business federal taxes for tax year 2026 are due in spring 2027: partnerships and S corporations file by March 15, 2027, and sole proprietors, single-member LLCs and C corporations file by April 15, 2027. If you pay estimated tax, your 2027 quarterly payments are due April 15, June 15 and September 15, 2027, and January 18, 2028.
Below is every key federal date for a calendar-year small business in 2027, taken from the IRS early release draft of Publication 509 (2027), with the weekend and holiday rule already applied. Pin it next to your desk, put the dates in your phone, and you will not get caught out.
Not tax advice. This is general information for US federal taxes. The 2027 Publication 509 is still a draft, so if the IRS publishes a different date, the IRS date wins. State and local deadlines are different. Check with a tax professional about your own situation.
The weekend and holiday rule
The IRS rule is simple: if a due date falls on a Saturday, Sunday or legal holiday, you are on time if you act by the next day that is not a Saturday, Sunday or legal holiday. "Legal holiday" means a legal holiday in the District of Columbia, which includes DC Emancipation Day on April 16.
In 2027 this rule moves three common deadlines:
- January 31, 2027 is a Sunday, so Forms W-2, 1099-NEC, 940 and the fourth quarter Form 941 move to Monday, February 1, 2027.
- July 31, 2027 is a Saturday, so the second quarter Form 941 moves to Monday, August 2, 2027.
- October 31, 2027 is a Sunday, so the third quarter Form 941 moves to Monday, November 1, 2027.
A statewide holiday can delay a filing deadline in some cases, but it never delays a federal tax deposit.
2027 federal tax deadlines at a glance
| Date (2027) | Who | What is due |
|---|---|---|
| Fri, January 15 | Individuals and sole owners | Fourth estimated tax payment for tax year 2026 |
| Mon, February 1 | Employers | Forms W-2 to employees, and W-2 with W-3 to the government |
| Mon, February 1 | Anyone who paid contractors | Form 1099-NEC to recipients and filed with the IRS |
| Mon, February 1 | Employers | Form 941 for the fourth quarter of 2026, and Form 940 for 2026 |
| Mon, February 1 | Individuals (optional) | File Form 1040 and pay in full instead of making the January 15 payment |
| Tue, February 16 | Businesses | Forms 1099-B, 1099-S and certain 1099-MISC amounts to recipients |
| Mon, March 1 | Businesses | Paper filing of most other Forms 1099 with the IRS (March 31 if filed electronically) |
| Mon, March 15 | Partnerships and multi-member LLCs | Form 1065 and partner Schedules K-1 for 2026 |
| Mon, March 15 | S corporations | Form 1120-S and shareholder Schedules K-1 for 2026 |
| Mon, March 15 | New S corporation | Form 2553 to be treated as an S corporation from 2027 |
| Thu, April 15 | Individuals and sole owners | Form 1040 or 1040-SR for 2026, or Form 4868 for an extension |
| Thu, April 15 | Individuals and sole owners | First estimated tax payment for 2027 |
| Thu, April 15 | C corporations | Form 1120 for 2026 (or Form 7004 for an extension) and first 2027 estimated payment |
| Fri, April 30 | Employers | Form 941 for the first quarter of 2027 |
| Tue, June 15 | Individuals and C corporations | Second estimated tax payment for 2027 |
| Mon, August 2 | Employers | Form 941 for the second quarter of 2027 |
| Wed, September 15 | Individuals and C corporations | Third estimated tax payment for 2027 |
| Wed, September 15 | Partnerships and S corporations | Extended Form 1065 or 1120-S, if you filed Form 7004 on time |
| Fri, October 15 | Individuals and C corporations | Extended Form 1040 or Form 1120, if you filed an extension on time |
| Mon, November 1 | Employers | Form 941 for the third quarter of 2027 |
| Wed, December 15 | C corporations | Fourth estimated tax payment for 2027 |
| Tue, January 18, 2028 | Individuals and sole owners | Fourth estimated tax payment for 2027 |
About that last line: the normal date is January 15, but January 15, 2028 is a Saturday and Monday, January 17, 2028 is Martin Luther King Jr. Day. Applying the IRS rule gives Tuesday, January 18, 2028. That date is our calculation, so confirm it on irs.gov when the 2028 calendar comes out.
If you deposit all of your payroll tax on time and in full, the IRS gives you extra days to file Forms 941 and 940 (February 10, May 10, August 10 and November 10 in 2027). The deposit itself is not extended.
Which deadline is yours?
Your business structure decides your main filing date.
- Sole proprietor or single-member LLC. Your business profit goes on Schedule C with your personal Form 1040, due April 15, 2027. You also pay self-employment tax on Schedule SE if your net earnings are $400 or more.
- Partnership or multi-member LLC. File Form 1065 by March 15, 2027 and give each partner a Schedule K-1. The partners then report their share on their own returns by April 15.
- S corporation (including an LLC that elected S status). File Form 1120-S by March 15, 2027, with K-1s to shareholders.
- C corporation. File Form 1120 by April 15, 2027 for a calendar year. Corporations pay estimated tax in April, June, September and December.
If your business uses a fiscal year instead of the calendar year, the dates shift. For example, Form 1040 is due on the 15th day of the 4th month after your tax year ends.
Quarterly estimated taxes, explained
No employer withholds tax from business profit, so the IRS expects you to pay during the year. Individuals, including sole proprietors, partners and S corporation shareholders, generally need to make estimated payments if they expect to owe $1,000 or more when they file. For corporations the line is $500. You use Form 1040-ES to work out and pay individual estimates.
The four payment periods do not line up with calendar quarters:
| Income earned | Payment due |
|---|---|
| January 1 to March 31, 2027 | April 15, 2027 |
| April 1 to May 31, 2027 | June 15, 2027 |
| June 1 to August 31, 2027 | September 15, 2027 |
| September 1 to December 31, 2027 | January 18, 2028 (see the note above) |
A worked example
Say you run a one-person cleaning business and expect a $40,000 profit in 2027. Here is a rough way to size your quarterly payments. These numbers are an example only; your own tax depends on your full situation.
- Self-employment tax is figured on 92.35% of net earnings: $40,000 x 0.9235 = $36,940.
- Self-employment tax at 15.3%: $36,940 x 0.153 = $5,651.82.
- Add an amount for federal income tax. As an example only, set aside 10% of profit: $4,000.
- Total to pay during the year: about $9,652, or about $2,413 per payment.
A quick way to run your own numbers is the free self-employed tax calculator. It gives you a set-aside amount, not a final tax bill.
Paying contractors? Watch the 1099-NEC date
If you paid an independent contractor for services, you may need to send them a Form 1099-NEC and file it with the IRS by February 1, 2027. For payments made after 2025, the reporting threshold for nonemployee compensation went up to $2,000. Collect a Form W-9 from each contractor when you start working with them, not in late January.
Extensions: more time to file, not to pay
Form 4868 (individuals) and Form 7004 (partnerships, S corporations and corporations) give an automatic 6-month extension to file. They do not give you more time to pay. Estimate what you owe and pay it by the original date, or penalties and interest can apply.
How to never miss a deadline
- Put every date above in your calendar now with a reminder one week ahead.
- Keep your books current every month. A deadline is only stressful when your numbers are a mess. A spreadsheet like the small business bookkeeping spreadsheet has Income, Expenses, Mileage, a Quarterly view and a Tax Summary, so your quarterly totals are ready when a payment is due.
- Move your tax set-aside on payday. Each time a client pays, move your percentage into a separate savings account.
- Use a printed calendar if that is how you work. The Small Business Tax Calendar 2027 puts these dates on a printable calendar with a quarterly estimated tax tracker.
- Check your state. State income tax, sales tax and franchise tax dates are set by your state and often differ from federal dates.
If you are still setting up your books, read how to track business expenses next.
Tools for this
Questions people ask
When are business taxes due for an LLC?
It depends on how the LLC is taxed. A single-member LLC taxed as a sole proprietorship reports on Schedule C with Form 1040, due April 15, 2027 for tax year 2026. A multi-member LLC taxed as a partnership files Form 1065 by March 15, 2027, and an LLC that elected S corporation status files Form 1120-S by March 15, 2027.
When are S corp business taxes due in 2027?
A calendar-year S corporation files Form 1120-S for 2026 by March 15, 2027, and gives each shareholder a Schedule K-1 by the same date. With a timely Form 7004 extension, the return is due September 15, 2027.
When are business taxes due with an extension?
An extension moves the filing date, not the payment date. Extended partnership and S corporation returns are due September 15, 2027, and extended Form 1040 and Form 1120 returns are due October 15, 2027. Any tax you expect to owe should still be paid by the original due date to avoid penalties and interest.
Do you have to pay quarterly taxes your first year in business?
You may. The IRS says individuals, including sole proprietors, partners and S corporation shareholders, generally need to make estimated payments if they expect to owe $1,000 or more when they file. For example, if your first year profit is $12,000, self-employment tax alone at 15.3% of about 92.35% of that profit is roughly $1,696, so quarterly payments are likely.
What happens if a tax deadline falls on a weekend?
The IRS treats an act as on time if it is done by the next day that is not a Saturday, Sunday or legal holiday in the District of Columbia. That is why the 2027 Form W-2 and Form 1099-NEC deadline is February 1 instead of January 31, which is a Sunday.
Sources
General information, not tax, legal or financial advice. Check the rules for your state and your situation.