What’s the deadline for Filing an Extension?
It's important to keep in mind that filing a federal extension only gives you more time to file your federal return — you’ll still need to pay any taxes you may owe.
Late Filing Penalty
To avoid the federally imposed 5% penalty on the amount of tax required, be sure to pay by the original IRS tax filing deadline (April 17, 2018).
Without proof of reasonable cause, if your federal tax return is not filed by the April 17th due date, or by the extended due date (if the extension request was filed timely) you will subject yourself to a 5% penalty towards the federal tax amount on the return required, (less any previous credits, payments applied) for the first month it is considered past-due, and an additional 5% for each month thereafter.
The penalty is capped at 25% of the amount of tax required, to be shown on the return (less any earlier payments and credits).
Late Payment Penalty
A late payment penalty, can also occur at ½% of 1%, on those federal taxes not paid by April 17th. And may also be charged for each, of the remaining months balance. Here again, the federal maximum penalty is 25%.
Federally imposed late payment penalties may be waived, if you can show reasonable cause during the extension duration, ‘if both of the following requirements are met’:
1. At least 90% of the total tax on your 2017 return is paid on or before the regular due date of your return through withholding, estimated tax payments, or payments made with Form 4868’.
2. The remaining balance is paid with your return.
There may be special rules for applying for a federal extension if you:
- Are serving in combat
- Live in a qualifying hazardous area
- Live outside of the United States
Please see this link for additional information.