How do I file a tax extension?

File IRS Form 4868 by the regular tax deadline (usually April 15) to get an automatic six-month extension to file your return. The extension gives you more time to file — not more time to pay. Any tax owed is still due by the original deadline.

An IRS tax extension is a formal request for more time to complete and submit your federal income tax return. Filing Form 4868 by the original due date — typically April 15 — gives you an automatic six-month extension, moving your filing deadline to October 15. The IRS approves it automatically; no explanation is required. What it does not do is extend the time to pay any tax you owe. Per IRS Form 4868 instructions, any balance due is still owed by the original April deadline to avoid interest and late-payment penalties.

How to file Form 4868

Online via IRS Free File: Visit irs.gov/freefile — you can e-file Form 4868 at no cost, even if your income is above the Free File threshold, since the extension form itself is always free.
IRS Direct Pay with extension designation: Paying any estimated balance due through IRS Direct Pay and selecting 'Extension' automatically files Form 4868 — no separate form submission needed.
Mail a paper Form 4868: Download, complete, and mail to the address listed in the instructions for your state. Must be postmarked by the original due date.
Through tax software: Most tax-preparation software (TurboTax, H&R Block, etc.) includes a one-click extension filing option.

Estimating and paying what you owe

To avoid a late-payment penalty (0.5% per month on the unpaid balance), estimate your tax liability as accurately as possible and pay any expected balance by the original deadline. Use your prior year's return as a starting point, adjust for major income changes, and pay via IRS Direct Pay or by check with Form 4868. If you overpay, the IRS will refund the difference after you file. If you underpay, interest accrues from the original due date — but you'll avoid the larger late-filing penalty (5% per month) by filing on time or with an extension.

State tax extensions

A federal extension does not automatically extend your state return. Most states grant their own extensions, but the rules vary: some require a separate form, some accept the federal extension, and some have different deadlines. Check your state's department of revenue website for state-specific guidance. The IRS state tax authority directory links to every state agency.

IRS extension facts

Filing Form 4868 by the regular due date gives taxpayers an automatic six-month extension of time to file their federal income tax return — no explanation or approval required. — IRS — Form 4868
An extension of time to file is not an extension of time to pay — interest and a late-payment penalty apply to any unpaid balance after the original due date. — IRS — Form 4868
Taxpayers can file Form 4868 electronically for free through IRS Free File, or pay an estimated balance through IRS Direct Pay and select 'Extension' to satisfy the filing requirement simultaneously. — IRS — Free File

Key takeaways

File Form 4868 by April 15 for an automatic six-month extension to October 15 — no IRS approval needed.
An extension extends the filing deadline only, not the payment deadline — any tax owed is still due April 15.
Pay your estimated balance by the original deadline to avoid the 0.5%/month late-payment penalty.
You can e-file Form 4868 free through IRS Free File, or combine payment and extension filing via IRS Direct Pay.
A federal extension does not cover your state return — check your state's own extension rules separately.