It’s almost April 18 (this year’s due date), and your taxes aren’t even close to being done.

But what if you don’t have all the information you need to complete your tax return? Or what if you just haven’t had time to sit down and do it?

There’s a quick and easy solution to avoid IRS penalties if you’re just not ready to file your tax return: File an extension.

If you won’t be able to finish and file your taxes by April 18, 2017, you can request an automatic 4-month extension using the free e-file version of Form 4868 right through the IRS website. And as long as you do it by April 18, your federal tax return will not be considered late.

Here’s the most important part: This is an extension of time to file the return, NOT an extension of time to pay any taxes you owe. If you expect to owe money, send in your estimated payment with the form – it will save you from costly interest and penalties later on.

Not sure how much you’ll owe? As long as you pay either the same amount you paid last year, or at least 90% of this year’s tax bill, you won’t get hit with an underpayment penalty.

If you think you’ll end up owing money, make sure to subtract all the tax payments you’ve already made – whether they were through payroll withholding or estimated tax payments – so you don’t end up paying extra.

And if you think you’ll be getting a refund, don’t send any money in with your extension.

What about my state income tax return?

The rules for extensions on state tax returns vary by state. Some automatically count your federal extension as a state extension. Others require you fill out a state form. Whatever the state rules are, the extension – just like the federal one – gives you only extra time to file…not extra time to pay.

Here’s a complete listing of state extension rules.