Important Federal Tax Dates for Small-Business Owners
Use this page as a quick reference for common federal filing and payment deadlines. Not every deadline applies to every taxpayer, and special rules can apply to fiscal-year businesses, disaster relief areas, and other situations.
Remaining 2026 deadlines
October 15, 2026
Extended deadline for most individual 2025 federal income tax returns when a timely extension was requested. An extension to file does not extend the time to pay tax due.
January 15, 2027
Fourth estimated tax payment for tax year 2026 is generally due for individuals who make quarterly estimated tax payments.
2027 filing season: key dates to plan for
January 31 / early February 2027
Businesses should be preparing year-end wage and information returns, including Forms W-2 and applicable Forms 1099. When a statutory due date falls on a weekend or legal holiday, the deadline generally moves to the next business day. Confirm the IRS-published 2027 filing calendar before filing.
March 15, 2027
General calendar-year deadline for partnership Form 1065 and S corporation Form 1120-S returns, based on the statutory filing rules. Confirm the final 2027 IRS calendar before filing.
April 15, 2027
General calendar-year deadline for individual Form 1040 returns and calendar-year C corporation Form 1120 returns, based on the statutory filing rules. This is also the general due date for the first 2027 individual estimated tax payment. Confirm the final 2027 IRS calendar before filing.
June 15, 2027
General due date for the second 2027 individual estimated tax payment.
September 15, 2027
General due date for the third 2027 individual estimated tax payment. This is also generally the extended filing deadline for calendar-year partnerships and S corporations that timely requested extensions.
October 15, 2027
General extended filing deadline for calendar-year individual returns when a timely extension was requested.
A note about estimated taxes
Quarterly estimated tax payments are not optional “quarterly tax returns.” They are payments toward the income tax and self-employment tax you expect to owe. The amount you need to pay depends on your own income, withholding, credits, prior-year tax, and other circumstances.
Need help?
Tax deadlines are only useful when they are connected to your actual tax situation. If you need help with tax preparation, estimated payments, planning, or an IRS matter, contact MTTA.
This calendar is provided for general informational purposes and is not a substitute for tax advice based on your specific facts. Deadlines may change because of weekends, legal holidays, disaster relief, legislation, or IRS guidance. MTTA recommends confirming deadlines that apply to your situation before filing or making a payment.