There are a few options when it looks like you’ll be unable to put that full payment into the mail to IRS by the 15th. First, be sure to file your return on or before April 15th. Secondly, include at least something toward what you owe. The government also offers options to taxpayers who have difficulty making full payment. One option is what’s called an “offer in compromise.” Another option that is rarely taken advantage of is a penalty abatement program for those who file or pay late. The IRS will OK a one-time waiver of late payment and late filing penalties of most individuals who have been tax compliant for the previous three years. This waiver must be requested; it is not offered and obviously not well known. If your tax preparer isn’t aware of the option, mention this!