What are the 2017 tax penalty amounts?
There are two tax penalties for late tax returns: The failure-to-pay penalty is 0.5% of your unpaid taxes, and the failure-to-file penalty is 5% of your unpaid taxes.
These penalties are added each month after the April 15 due date. If you’re more than 60 days late, the minimum penalty is the smaller of $135 or 100% of the unpaid tax. To avoid a failure-to-file penalty, file by the April 15 due date or file for a six-month extension by the April 15 due date using IRS Form 4868. The extension will give you until October 15 to file your taxes.