IRS Advances Stalled Nonfiler Cases Following Inspector General Audit
The Internal Revenue Service advanced nearly 39,000 high-priority tax cases involving high-income nonfilers after a Treasury Inspector General for Tax Administration (TIGTA) audit revealed extensive processing delays. The cases had stalled at the first-notice stage rather than advancing to final enforcement notices within the standard eight-week timeframe. According to the watchdog report released on September 4, these stalled cases represented approximately $15.7 billion in potential tax assessments. In response to TIGTA's alert and six recommendations, the IRS corrected the underlying issues and moved the affected cases forward in March 2026.
The affected accounts were monitored under a high-income nonfiler initiative launched by the IRS in February 2024. The program tracked 135,270 cases targeting individuals with incomes of $400,000 or more, federal employees, IRS staff, and individuals identified through a Senate Finance Committee request. TIGTA analyzed 111,566 of those cases after excluding ineligible accounts, finding that as of June 30, 2025, 81,417 cases—or 73 percent—remained without a filed return or tax assessment. Of those, 38,824 cases involving 33,653 taxpayers were stuck in first-notice status.
TIGTA identified both system errors and administrative delays as the root causes of the stalling. In March 2024, IRS collection function management requested that final notices be delayed due to concerns over available staffing resources, preventing cases from progressing through delinquent collection steps. Additionally, 10,969 high-priority cases involving $2.5 billion in potential tax liabilities were stuck in the collection queue waiting for assignment as of June 30, 2025, though the IRS reduced that queue backlog to 9,463 cases by December 31, 2025.
The audit also revealed administrative missteps affecting compliant filers. The IRS issued initial nonfiler notices to 4,918 cases involving 4,748 taxpayers who had already submitted their tax returns. TIGTA reported that these taxpayers were incorrectly caught in the initiative because the IRS failed to process and post their filed returns in a timely manner, with 1,433 returns taking more than a year to post to account records.
For high-income taxpayers with delinquent returns, the resolution of these notice delays signals a swift resumption of IRS enforcement activity. As the agency moves these cases out of initial status, affected taxpayers face a heightened likelihood of receiving final notices and potential collection enforcement, such as levies or liens. TIGTA estimated that earlier action could have led to returns or assessments in 10,482 cases involving approximately $321.3 million in additional tax, which the IRS can still seek to collect.
The report emphasized broader structural issues within the IRS, noting that the agency lacks coordinated oversight for nonfiler programs and prioritizes existing balance-due accounts over unfiled returns. TIGTA noted that the agency's Nonfiler Executive Steering Committee has not met since September 2020 and that the IRS does not separately track nonfiler program resources. Addressing nonfiler enforcement remains critical for the agency, as nonfilers accounted for an estimated $63 billion of the $696 billion gross tax gap estimated for tax year 2022.
Source: Journal of Accountancy
