<prompt> Human: Basically Im an idiot and thought all my stuff would be efiled on April 17. However apparnetly I was supposed to mail my payment in while only my documents would be eFiled.What sort of penalties can I expect for being 2 days late with mailing the check? Will they contact me with penalties or do I calculate those on my own? Ive never been late before, what happens in this situation? I am kind of freaking out.Assistant: They will tell you if you owe any interest or penalties. They will be minimal.Penalty for late payment. The failure-to-pay penalty is generally 0.5 percent per month of your unpaid taxes. It applies for each month or part of a month your taxes remain unpaid and starts accruing the day after taxes are due. It can build up to as much as 25 percent of your unpaid taxes.Human: So will they mail me something? When would I receive that? Is it .5 per day late?  <response>: They also extended the deadline to Apr 18, so you would only be one day late. 