The head of the IRS has a message for taxpayers and tax preparers who have endured long wait times while on the phone with the tax agency: Call your member of Congress.

During his keynote speech at the 69th Annual Meeting of the National Society of Accountants (NSA) in Baltimore on August 21, IRS Commissioner John Koskinen said the biggest challenge facing the IRS is trying to implement tax provisions of the Affordable Care Act while the agency’s budget for fiscal year 2014 was slashed by 7 percent.

“As I tell people on Capitol Hill, we are the only agency still operating at the post-sequester level,” Koskinen said, according to an article posted on the NSA website.

In her annual report to Congress earlier this year, National Taxpayer Advocate Nina Olson said budget reductions have significantly hampered the IRS’s ability to provide “top-quality service” and “maintain effective enforcement programs that minimize noncompliance.”

For example, only 61 percent of the more than 100 million customer service phone calls made to the IRS last year were answered, according to the report. Telephone wait times increased from 2.6 minutes a decade ago to 17.6 minutes in 2013.

During his speech on Thursday, Koskinen said his agency was forced to cut 5,200 call center employees because of budget cuts, and he warned that wait times for phone service will increase through the rest of the year because of a lack of staff.

“People don’t vote for me; they vote for members of Congress,” Koskinen stated. “Congress needs to hear and understand the impact of the funding cuts.”

The IRS chief also doesn’t understand why Congress would reduce funding for the federal government’s top revenue-generating function at a time when a revenue shortage continues to force budget cuts. Koskinen has noted in the past that the US government is losing billions in revenue collection to achieve budget savings of a few hundred million dollars. The IRS has estimated that for every $1 invested in the agency’s budget, it produces $4 in revenue.

“Congress is starving our revenue-generating operation,” he said on Thursday. “If voluntary compliance with the tax code drops by 1 percent, it costs the US government $30 billion per year. The IRS budget is only $11 billion per year.

“[Congress] cannot continue to reduce our resources and ask us to do more things,” Koskinen added. “The blind belief in Congress that they can continue to cut funding and we will just become more efficient is not the case. We are becoming more efficient, but there is a limit. Eventually the effects will show up. We are no longer going to pretend that cutting funding makes no difference.”

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