The Internal Revenue Service’s updated contingency plans for a government shutdown include furloughing 60,000 employees, about two thirds of its total workforce, Federal News Network (FNN) reported.

The rest, about 30,000, will remain on the job and be paid through Inflation Reduction Act funds and fees, as well as revenue from private debt collectors the IRS is required by Congress to employ to collect certain outstanding tax debts.

A Treasury spokesperson told FNN that a mostly furloughed IRS workforce will have “significant impacts” on taxpayers, and that most of the IRS’s core tax administration functions would stop during a shutdown.

Earlier this week, the labor union that represents IRS workers, the National Treasury Employees Union (NTEU) said that the agency was preparing for a possible government shutdown by developing a contingency plan that could mean service cutbacks due to furloughs. That updated plan was released yesterday.

On Sept. 13, the NTEU said that the IRS would remain “fully operational” in the event of a shutdown, which would occur after Sept. 30 if Congress did not appropriate the necessary funding to keep the government running into the next fiscal year. Eight days later, on Sept. 21, FNN reported the NTEU’s saying that the IRS would “partially close” if no money is appropriated.

“NTEU remains concerned about the stress that thousands of IRS workers in every state are dealing with right now knowing their income is in jeopardy,” NTEU President Greenwald told FNN. “An additional worry is the impact the shutdown will have on IRS efforts to hire to prevent further backlogs and delays that American taxpayers are likely to experience.”

The IRS will not process tax refunds during a shutdown, except in cases where electronically filed, error-free refunds can be direct-deposited automatically. The IRS will continue to receive mail during a government shutdown, as the U.S. Postal Service is generally self-funded and would not be affected by a shutdown, but will not respond to correspondence.

The IRS will still process requests for tax transcripts following disasters, and provide income verification to mortgage lenders, banks, and others who request this information through the agency’s Income Verification Express Service (IVES) program.

In her last blog of the current fiscal year, National Taxpayer Advocate Erin Collins wrote that her office would not be able to assist taxpayers in the event of a shutdown.