The Internal Revenue Service today urged taxpayers whose tax-filing extension runs out on Oct. 15 to double check their returns for often-overlooked tax benefits and then file their returns electronically using IRS e-file or the Free File system.

Before filing, the IRS encourages taxpayers to take a moment to see if they qualify for these and other often-overlooked credits and deductions:

More than a quarter of the nearly 13 million taxpayers who requested an automatic six-month extension this year have yet to file. Although Oct. 15 is the last day for most people, some still have more time, including members of the military and others serving in Afghanistan or other combat zone localities who typically have until at least 180 days after they leave the combat zone to both file returns and pay any taxes due.

At the same time, IRS also urged taxpayers to choose the speed and convenience of electronic filing. IRS e-file is fast, accurate and secure, making it an ideal option for those rushing to meet the Oct. 15 deadline. The tax agency verifies receipt of an e-filed return, and people who file electronically make fewer mistakes too. Of the more than 143 million returns received by the IRS so far this year, 85 percent or nearly 122 million have been e-filed.