The returns piled up last year because most of the IRS staff was not in government offices to process the paper during the pandemic.

As of June 10, more than 4.5 million of 4.7 million 1040 returns received in 2021 had been processed. The vast majority of tax returns received this year have been processed, the IRS said.

The IRS said efforts to handle unprocessed inventory of returns and correspondence by the end of this year include "aggressive, unprecedented steps to accelerate this important processing work while maintaining accuracy.” Those efforts included newly created  special teams of employees focused on the backlog with plans to hire thousands of new employees and contractors as part of the effort.

Additionally, it said a process was established to speed error resolutions. During the 2021 filing season, the IRS reported a tax examiner could correct an average of 70 returns with errors per hour. Technology implemented for the 2022 filing season has sped this up to 180 to 240 returns per hour.

There were 8.9 million tax returns in error resolution as of June 12 2021. As June 10, 360,000 returns were awaiting correction.

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