2026 Tax Deadlines You Can’t Afford to Miss

Official IRS Dates Every Self-Employed Person & Small Business Must Know

You know April 15th.
But did you know March 15th is the absolute deadline to elect S-Corp status for 2026 tax savings?
Or that January 15th is your last chance to pay 2025 estimated tax without penalties?

According to IRS Publication 509 (Tax Calendars for 2026), missing even one key date can trigger fees, disqualify you from relief programs, or cost you thousands in missed deductions.

Let’s walk through the official 2026 deadlines—straight from the IRS—that affect sole proprietors, freelancers, LLCs, and S-Corps.

🗓️ January 2026

✅ January 15: Final 2025 Estimated Tax Payment (Q4)

  • Who it affects: Self-employed, gig workers, investors, retirees with no withholding
  • IRS source: Pub 509, General Tax Calendar, p. 3
  • Why it matters: This is your last chance to avoid underpayment penalties for 2025—even if you file an extension in April.
  • Tip: Use Form 1040-ES or pay electronically via EFTPS or IRS Direct Pay.

🗓️ February 2026

✅ February 2: 1099 Forms Due to Recipients

  • Who it affects: Any business that paid contractors $600+ in 2025
  • Forms: 1099-NEC (nonemployee compensation), 1099-MISC, 1099-K, etc.
  • IRS source: Pub 509, p. 3
  • Note: 1099-NEC must be sent by Feb 2—not March like other 1099s.

🗓️ March 2026

✅ March 15: S-Corp & Partnership Returns Due

  • Forms: 1120-S (S-Corps), 1065 (Partnerships)
  • IRS source: Pub 509, p. 4
  • Penalty: $220/month per owner for late filing
  • Extension: File Form 7004 → extends to September 15

✅ March 15: S-Corp Election Deadline for 2026

  • Form: 2553 (“Election by a Small Business Corporation”)
  • IRS rule: Must be filed no later than 2 months and 15 days after the start of the tax year
  • Consequence: Miss this, and you lose S-Corp status—and SE tax savings—for all of 2026

🗓️ April 2026

✅ April 15: Individual Tax Returns Due (2025)

  • Forms: 1040 or 1040-SR + Schedule C
  • Also due:
    • Q1 2026 estimated tax payment
    • 2025 IRA/HSA contributions (for prior-year deductions)
    • Solo 401(k) plan setup (to contribute for 2025)
  • IRS source: Pub 509, p. 4

✅ Need more time? File Form 4868

  • Gives you until October 15 to file
  • BUT: You must still pay any tax owed by April 15 to avoid penalties (Pub 509, p. 4)

🗓️ June 2026

✅ June 15: Q2 2026 Estimated Tax Payment Due

  • Also: Extended deadline for U.S. citizens living abroad to file 2025 returns (Pub 509, p. 4)

🗓️ September 2026

✅ September 15: Q3 2026 Estimated Tax Payment Due

  • Also: Extended deadline for S-Corps & Partnerships (if Form 7004 filed) (Pub 509, p. 5)

🗓️ October 2026

✅ October 15: Extended Individual Returns Due

  • Final deadline if you filed Form 4868 (Pub 509, p. 5)

⚠️ Critical Reminder: State Deadlines Vary

The IRS calendar covers federal dates only.

  • California FTB, New York DTF, and Texas Comptroller all have their own rules
  • Some states (like CA) charge higher penalties for late filing

🔍 Action step: Google “[Your State] Department of Revenue 2026 tax deadlines”

🎁 Free Download: 2026 IRS Tax Deadline Tracker

👉 Get it free—no email required:
[Download the 2026 IRS Tax Deadline Tracker (PDF)]

Print it. Tape it to your desk. Set phone reminders.
Your future self will thank you.

Final Thought

These aren’t arbitrary dates.
They’re legal requirements set by the IRS to keep the system fair and functional.

And remember—you don’t have to track them alone.
— Uncle Joe

P.S. Share this with a freelancer or S-Corp shareholder. One date could save them thousands