The U.S. Internal Revenue Service provided live assistance to 87% of taxpayers' phone calls during the 2023 tax filing season, up from 15%, due to customer service hires made possible by $80 billion in new IRS funding over a decade, the U.S. Treasury said Monday.

As Tuesday's tax filing deadline approached, the Treasury said that the 5,000 new IRS staff enabled the agency to answer 2.4 million more calls during the 2023 tax filing season through April 7 than the 2022 season, with call waiting times down to four minutes from 27 minutes.

Including the new 5,000 taxpayer services personnel, the IRS plans to hire some nearly 20,000 new staff over two years as it deploys new funding from the climate-focused Inflation Reduction Act.

Republicans in the U.S. House of Representatives have targeted the $80 billion in new IRS funding as part of their spending cut demands in exchange for raising the $31.4 trillion U.S. debt ceiling. The funding, aimed at beefing up enforcement and audits for wealthy taxpayers and business partnerships, modernizing computer systems and improving taxpayer services, comes on top of the agency's annual operating budget.