Treasury Inspector General for Tax Administration – High-Income Nonfilers Owing Billions of Dollars Are Not Being Worked by the Internal Revenue Service May 29, 2020, Reference Number: 2020-30-015: “The gross Tax Gap is the estimated difference between the amount of tax that taxpayers should pay and the amount paid voluntarily and on time. The average annual gross Tax Gap is estimated to be $441 billion for Tax Years 2011 through 2013, and approximately $39 billion (9 percent) is due to nonfilers, taxpayers who do not timely file a required tax return and timely pay the tax due for such delinquent returns. According to the IRS, high-income nonfilers, although fewer in number, contribute to the majority of the nonfiler Tax Gap…

• The IRS did not work 369,180 high-income nonfilers, with estimated tax due of $20.8 billion. Of the 369,180 high-income nonfilers, 326,579 were not placed in inventory to be selected for work and 42,601 were closed out of the inventory without ever being worked. In addition, the remaining 510,235 high-income nonfilers, totaling estimated tax due of $24.9 billion, are sitting in one of the Collection function’s inventory streams and will likely not be pursued as resources decline.
• The IRS removed high-income nonfiler casesfrom inventory, resulting in 37,217 cases totaling $3.2 billion in estimated tax dollarsthat will not likely be worked by the IRS…”