When Are Taxes Due 2026? Full Tax Filing Deadline Calendar

Taxes are due April 15, 2026 for most individuals and C-corporations filing their 2025 tax return. Partnerships and S-corporations had an earlier deadline of March 16, 2026. Filers who requested an extension have until October 15, 2026 (September 15 for pass-through entities) — but any tax owed was still due April 15.

Updated August 2026 — this page tracks every remaining 2026 tax deadline as the year progresses.

Key takeaways

• When are taxes due 2026: April 15, 2026 for individuals (Form 1040) and C-corporations (Form 1120).
• Tax deadline 2026 for pass-through businesses: March 16, 2026, for partnerships (Form 1065) and S-corporations (Form 1120-S).
• Deadline to file taxes 2026 with an extension: October 15, 2026 for individuals and C-corps; September 15, 2026 for partnerships and S-corps.
• Tax season 2026 ran from January 26 (IRS filing season open) through April 15 (filing deadline), with a second window through October 15 for extension filers.
• Next deadline coming up: Q3 2026 estimated tax payment, due September 15, 2026.

What’s due next (as of today)

If you already filed your 2025 return, here’s what’s still on your calendar:

When are taxes due 2026?

Taxes were due April 15, 2026 for most individual and C-corporation returns covering the 2025 tax year. Partnerships and S-corporations had an earlier deadline of March 16, 2026. If you filed an extension, your new filing deadline is October 15, 2026 — but any tax owed still needed to be paid by April 15 to avoid interest and penalties.

This is the answer whether you’re searching “when are taxes due,” “tax deadline 2026,” “deadline for taxes 2026,” or “when is the income tax deadline” — they’re all pointing at the same date: April 15, 2026 (or March 16 for partnerships and S-corps).

Tax Day 2026

Tax Day is the annual federal deadline to file individual income tax returns and pay any tax owed. It’s set at April 15 each year, unless that date falls on a weekend or federal holiday, in which case it moves to the next business day. Tax Day 2026 fell on Wednesday, April 15, 2026.

Deadline to file taxes 2026 / Last day to file taxes 2026

For individuals who didn’t request an extension, the last day to file taxes 2026 was April 15, 2026. For anyone who filed Form 4868, the extended deadline to file taxes 2026 is October 15, 2026. Businesses taxed as partnerships or S-corporations had an earlier deadline — March 16, 2026 — with an extended deadline of September 15, 2026.

When can I file my taxes for 2025?

The IRS opened the 2026 filing season and began accepting 2025 tax year returns on January 26, 2026. IRS Free File opened even earlier, on January 9, 2026, for qualifying taxpayers. So if you’re asking “when can I file my taxes,” the window runs from late January through the April 15 deadline — and you can file the moment the IRS starts accepting returns, without waiting until the deadline approaches.

When is tax season?

Tax season runs from late January, when the IRS opens e-filing, through April 15, the filing deadline. For 2026, that window was January 26 – April 15. A second, quieter tax season runs through October 15 for anyone on extension.

When does tax season start 2026? January 26, 2026, when the IRS began accepting individual returns (IRS Free File opened January 9).

When does tax season end? The main filing window ends April 15. For extension filers, the practical “end” of tax season is October 15 (or September 15 for partnerships and S-corps).

Tax extension deadline 2026

If you filed Form 4868 (individuals) or Form 7004 (businesses) by the original April 15 or March 16 deadline, here’s where your extended deadline landed:

• Individuals & C-corporations: extended to October 15, 2026
• Partnerships & S-corporations: extended to September 15, 2026

An extension moves your filing deadline, not your payment deadline. At least 90% of what you owed needed to be paid by the original due date to avoid a failure-to-pay penalty — this is the detail people searching “deadline of filing tax” most often miss. You can request an individual extension using IRS Form 4868.

Full 2026 tax due date calendar

US tax filing deadline 2026 for businesses

Business filing dates depend on entity type and fiscal year — this is where most business tax deadline 2026 confusion starts, since businesses juggle payroll, pass-through, and entity-level dates that all land differently.

• Partnerships & S-corporations (calendar year): Form 1065 or 1120-S due March 16, 2026; extended deadline September 15, 2026.
• C-corporations (calendar year): Form 1120 due April 15, 2026; extended deadline October 15, 2026.
• Fiscal-year businesses: returns are generally due the 15th day of the third month (pass-through) or fourth month (C-corp) after your fiscal year ends — not tied to the calendar-year dates above.
• Payroll reporting: W-2s and 1099-NECs were due to employees and contractors by February 2, 2026 (moved from the usual January 31, which fell on a weekend).

LLC tax filing deadline 2026

An LLC’s deadline depends entirely on how it’s taxed, not on the fact that it’s an LLC:

• Single-member LLC (taxed as a sole proprietorship): filed with your personal return — due April 15, 2026.
• Multi-member LLC (default taxed as a partnership): due March 16, 2026, filed on Form 1065.
• LLC taxed as an S-corporation: due March 16, 2026, filed on Form 1120-S.
• LLC taxed as a C-corporation: due April 15, 2026, filed on Form 1120.

If you’re not sure how your LLC is taxed, check the election filed with the IRS (or ask your accountant) before assuming your deadline — filing on the wrong date is one of the most common LLC penalty triggers.

Quarterly estimated tax payments

Self-employed professionals, freelancers, investors, and business owners without withholding pay estimated tax four times a year:

• April 15, 2026 — Q1
• June 15, 2026 — Q2
• September 15, 2026 — Q3
• January 15, 2027 — Q4

Paying 90% of your current-year liability, or 100–110% of last year’s (depending on income), generally avoids an underpayment penalty even if your estimate isn’t exact.

When are taxes due 2025?

For reference: taxes for the 2024 tax year (filed in 2025) were due April 15, 2025, with partnerships and S-corporations due March 17, 2025. That deadline has already passed. If you never filed a 2024 return, file as soon as possible — the failure-to-file penalty keeps accruing (up to 25% of unpaid tax), and if you’re owed a refund, you generally have three years from the original due date to claim it before it becomes the property of the U.S. Treasury.

What happens if you miss a deadline?

This depends on whether you owe money or are due a refund.

If you’re owed a refund: There’s typically no penalty for filing late. You generally have three years from the original due date to claim it — for a 2025 return due April 2026, that window closes in 2029. After that, an unclaimed refund becomes the property of the U.S. Treasury.

If you owe taxes: The IRS begins charging a failure-to-file penalty (up to 5% of unpaid tax per month, capped at 25%) plus a separate failure-to-pay penalty and interest starting the day after the deadline. Filing immediately — even without full payment — stops the larger failure-to-file penalty from continuing to accrue.

If you missed a quarterly estimated payment: Pay it as soon as possible. The penalty scales with how much you owe and how late you are, so speed matters more than precision.

If you can’t pay what you owe: File on time regardless, pay what you can, and set up an IRS payment plan for the rest. Not filing because you can’t pay in full is the costliest mistake — it triggers the larger of the two penalties for no benefit.

Disaster-area extensions: If you’re in a federally declared disaster area, the IRS often automatically postpones both filing and payment deadlines. Check IRS.gov for current disaster relief declarations if this applies to you.

How KMK Ventures keeps you ahead of every deadline

Missing a tax preparation deadline is rarely about not knowing the date — it’s about records not being ready in time: late payroll data, incomplete books, or not enough internal bandwidth during the January–April crunch. KMK Ventures provides:

• Accounting and bookkeeping support
• Tax preparation assistance
• Payroll processing support
• Financial reporting
• Scalable finance teams that flex up during tax season without a permanent headcount increase

Read next: S Corp Tax Return Deadline 2026: Key Dates, Filing Checklist, and Penalties