14 Last-Minute Tax Tips: Don't Leave Money on the Table

14. Cover yourself to avoid a penalty

The IRS asks you to calculate your tax liability for the year when you file for an extension. You may think, if I already knew my tax liability, I wouldn’t be filing for an extension; I’d be filing my 1040 and be done with it!

But still, an extension can give you a little breathing room to do your return right. You can highball your estimated liability and send in a payment with your 4868, and get that money back as a refund when you do file your return.