Individual Extension Deadline — October 15
Thursday, October 15, 2026
Final extended deadline to file your 2025 individual federal tax return — October 15, 2026.
Who must file or pay
Taxpayers who filed Form 4868 (extension) by April 15. The extension gives 6 additional months to FILE — not 6 months to pay.
What you need to know
If you filed Form 4868 by April 15, 2026, your 2025 individual federal return is due October 15, 2026. This is the absolute final deadline — no further extensions are available beyond this date.
The extension only extends the time to file, not the time to pay. Any tax owed was due April 15. If you underpaid, interest and the failure-to-pay penalty (0.5%/month) have been accruing since then.
October 15 is also the deadline for establishing and funding a SEP-IRA for 2025 if you have not already done so (if you extended your return). This makes the extended deadline a final opportunity for meaningful retirement contribution deductions. Genie can calculate your maximum SEP-IRA contribution based on your 2025 self-employment income.
If you owe tax and have not paid by April 15, failure-to-pay penalties and interest continue to accrue through October 15. After October 15, failure-to-file penalties recommence on any remaining unfiled returns.
Required forms
- →Form 1040
- →Form 4868 (already filed to get the extension)
A licensed TaxosAgent professional reviews your situation before this deadline — so you maximize savings, not just compliance.
Book a strategy call→Free audit first →guaranteed, or your money back.
Other dates to know
Individual Tax Return Deadline — April 15
Federal individual income tax return due April 15, 2026 for tax year 2025.
C-Corp Extended Deadline — October 15
Final extended deadline for C-Corporation Form 1120 — October 15, 2026.
IRA / Roth IRA Contribution Deadline — April 15
Traditional IRA and Roth IRA contribution deadline for 2025 tax year — April 15, 2026. SEP-IRA deadline extended if you file an extension.