The 2027 tax deadline is the date most people search for each spring. The federal rule is simple: returns are due on April 15, and if that day is a weekend or legal holiday, the next business day. The extra dates, for extensions and for people living abroad, are where mistakes happen.
This guide gives the 2027 dates for 2026 returns, what an extension does and does not cover, and the penalties for filing or paying late, with a worked example. It follows IRS Topics 301, 304 and 653 and the Form 4868 instructions.
| What | Date | How we know |
|---|---|---|
| Tax return and payment due | Thursday, April 15, 2027 | IRS: for the 2025 return the due date is April 15, 2026; the same April 15 rule gives April 15, 2027, which is a Thursday |
| Extension of time to file (Form 4868) | Friday, October 15, 2027 | IRS: an extension runs up to 6 months, October 15, 2026 for most calendar-year taxpayers in the 2025 cycle |
| Taxpayers abroad (automatic 2 extra months) | Tuesday, June 15, 2027 | IRS: generally until June 15 for U.S. citizens and resident aliens living or serving outside the U.S. and Puerto Rico |
The 2027 dates above follow the IRS rule from the 2025 cycle. Confirm them on the IRS website when the 2026 Form 1040 instructions are published. If a due date falls on a Saturday, Sunday or legal holiday, the IRS moves it to the next business day, so check the calendar for the year you are filing.
There are three ways to request an automatic extension of time to file: pay all or part of your estimated tax and indicate the payment is for an extension, e-file Form 4868, or file a paper Form 4868. An extension of time to file is not an extension of time to pay: tax unpaid by the April due date still builds interest. Several companies offer free filing of Form 4868 through the Free File program. See our Form 4868 extension guide for the steps.
| Penalty | Rate | Cap |
|---|---|---|
| Failure to file | 5% of the tax owed for each month or part of a month the return is late | 25% |
| Failure to pay | 0.5% of the unpaid tax for each month or part of a month | 25% |
| Minimum failure-to-file penalty (return over 60 days late) | The lesser of $535 (for returns required to be filed in 2027, which includes 2026 returns filed on time) or 100% of the tax owed | - |
The $535 minimum for returns required to be filed in 2027 comes from Rev. Proc. 2025-32, section 4.52. For returns required to be filed in 2026 (2025 tax year), IRS Topic 653 gives $525. The minimum applies only when the return is more than 60 days late.
Suppose you owe $3,000 in tax. These are separate illustrations of each penalty; the IRS can apply both, so see IRS Topic 653 for how they combine.
| Scenario | Calculation | Penalty |
|---|---|---|
| File on time with an extension and pay the $3,000 six months late (on October 15) | 0.5% x 6 months x $3,000 | $90.00 |
| No extension, file the return three months late | 5% x 3 months x $3,000 | $450.00 |
Interest is charged on top. The comparison shows why filing on time, even without full payment, is usually cheaper than not filing.
Estimated-tax payments, state deadlines and employer forms have their own dates. Our quarterly estimated tax guide covers quarterly dates, and state returns can differ from the federal deadline, so check your state tax agency.
IRS Topic no. 301: When, how and where to file, IRS Topic no. 304: Extensions of time to file, IRS Topic no. 653: Penalties and interest, IRS Form 4868 and instructions, Rev. Proc. 2025-32 (2026 inflation adjustments, section 4.52).