When are taxes due in the US?
Generally, your tax return must be postmarked no later than April 15, or sent no later than that date if you're filing electronically. Sometimes the date is extended due to a weekend or local DC holiday.
In 2011, taxes must be filed by April 18.
In 2011 the IRS is giving you three extra days to file your tax return. This is due to a local-D.C. holiday known as Emancipation Day (celebrated on Friday, April 15). Thus, the tax deadline has been pushed to Monday, April 18, 2011.
Procrastinating with taxes is a familiar phenomenon, but if you don't pull it together before the deadline, things can get tricky. If you know you won't be able to file on time, or don't have the money to pay, don't ignore your taxes altogether. File an extension form on time and look into a payment plan. The IRS charges interest and does collect. Extensions of time to file (for 6 months), BUT NOT TO PAY, are virtually automatic, however you must estimate your tax due and make sure it is all paid when requesting an extension.
Taxes are paid throughout the year, by different forms of withholding on income (or payroll) and by estimated payments if self employed. Failing to do so is illegal, and incurs a penalty and interest charge. The tax filing is due by 4/15 of the year following the year being reported, for most people.