IRS Is Falling Further Behind on Tax-Return Backlog, Watchdog Says

WASHINGTON—The Internal Revenue Service faces daunting mathematical and logistical challenges in its attempt to largely eliminate its tax-return backlog by the end of 2022, an agency watchdog said Wednesday.

The backlog of unprocessed paper tax returns was 21.3 million at the end of May, up 1.3 million from a year earlier, according to Erin Collins, the national taxpayer advocate, who runs an independent taxpayer-service operation within the IRS. Agency officials have said they aimed to return the backlog to a “healthy” level in the next six months.