Tax Filing Extensions: Don't Just Add Six Months

Filing an extension feels like simple arithmetic: take the deadline, add six months, done. The US tax calendar is rarely that tidy.

The deadline shifts off weekends and holidays

When a statutory deadline lands on a Saturday, Sunday, or legal holiday, it rolls to the next business day. That's why the familiar April 15 date moves around year to year — and why the extended deadline can land a day or two off from the naive "add six months" answer.

The Emancipation Day wrinkle

Emancipation Day, a holiday observed in Washington, D.C., can push the federal filing deadline even when it isn't a nationwide holiday. It's a classic example of a closure most people don't have on their mental calendar quietly moving a federal date.

Compute the extended date

The Tax Filing Deadline Extender calculator applies the weekend-and-holiday roll-forward rules so the extension date you write down is the one that actually governs.

General information only — not tax advice. Verify with the IRS or your preparer.