Filing a tax extension? You still have to pay on time.

Tax Day is here, which means people who haven't done their taxes yet will be filing for a six-month extension. But the extension gives you more time to file, not more time to pay – with a few notable exceptions.  

The Internal Revenue Service Headquarters (IRS) building in Washington. Wednesday, April 15, 2015, is the deadline for filing income tax returns, a day long associated with the dread of rushing to fill out complicated forms and, perhaps, making a payment to Uncle Sam.

David Ake/AP/File

April 15, 2015

The April 15 tax deadline is here, and people who haven’t done their taxes yet will probably be filing a six-month extension unless they plan to spend the weekend knee-deep in paperwork.

But before you assume you can forget about your taxes for the next six months, consider a few important points that can keep you from being penalized by the Internal Revenue Service.

If you are not going to have your tax return done on time, you can ask for an automatic six-month extension to get your information together. That will give you until October 15. To ask for an extension, you can fill out Form 4868, which is an Application for an Automatic Extension of Time to File a U.S. Individual Income Tax Return.

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However, that gives you more time to file, not more time to pay. Your taxes are due on April 15, whether or not you submit your tax return. Before you file your extension, figure out whether you’re going to owe the IRS money and consider sending the agency a check with the application for an extension.

Now for a little secret: You can also get an extension for your payment, in certain circumstances, by filing Form 1127, which is an Application for Extension of Time for Payment of Tax Due To Undue Hardship. Less than 10% of these requests are granted each year. However, if you are experiencing extreme financial hardship, think about filing this request.

Here’s another little-known fact: If you owe money to the IRS, and you don’t pay it by April 15, you can get a one-time “oops” waiver of your penalties. If you made a one-time mistake, you can write to the IRS and request abatement of the penalty. If this is your first time making that mistake, the IRS may decide not to penalize you for failing to pay your taxes on time. However, the agency won’t give you the waiver unless you ask for it.

So remember, just because you filed an extension for your tax return doesn’t mean you’re in the clear. Be very careful and pay your taxes by April 15. If you don’t, ask the IRS to waive the penalties. That way you’ll stay on the good side of the taxman.

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