• President-elect Donald Trump will nominate former Missouri congressman Billy Long to lead the IRS.
• The announcement signals plans to fire the current IRS Commissioner Daniel Werfel before his term ends in 2027, which is permitted by law.
• Responses have been mixed in Washington and the tax community.

President-elect Donald Trump has tapped former Missouri congressman Billy Long to lead the IRS, which has triggered mixed reactions from Washington and the tax community.

If confirmed, Long could mean a shift for the agency, which has embarked on a multibillion-dollar revamp, including upgrades to customer service, technology and a free filing program. The agency has also expanded enforcement to collect unpaid taxes from wealthy individuals, large corporations and complex partnerships.

In 2022, Congress approved nearly $80 billion in IRS funding, which has been targeted by Republicans and could be at risk under the Trump administration.

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"Since leaving Congress, Billy has worked as a business and tax advisor, helping small businesses navigate the complexities of complying with the IRS Rules and Regulations," Trump wrote in a Truth Social post on Wednesday. "Taxpayers and the wonderful employees of the IRS will love having Billy at the helm."

Long worked as an auctioneer before serving six terms in the House of Representatives from 2011 to 2023.

Trump's announcement signals plans to fire the current IRS Commissioner Daniel Werfel before his term ends in 2027, which is permitted by law. Werfel was appointed by President Joe Biden and has led the agency since 2023.

Long is 'an unconventional pick'

Former IRS Commissioner Charles Rettig, who served under Trump and Biden from 2018 to 2022, said he doesn't know Long, or whether Long and Werfel have discussed the transition.

If confirmed to succeed Werfel, "I'm hopeful Billy Long will quickly grasp the importance of the IRS and of the IRS employees to the overall success of our country," he told CNBC in an email.

Mark Everson, who served as IRS commissioner from 2003 to 2007, described Long as "an unconventional pick," compared with the experience profiles of previous IRS leaders. 

But Long's years in Congress will provide "credibility up on the Hill with the people who matter, which will be important," said Everson, who is currently vice chairman at Alliant, a management consulting company.

Long may be in a "better position than others to argue for the appropriate independence of the agency," he said.

But some Democrats expressed concerns over Trump's nominee.

"There are a lot of reasons why former Congressman Billy Long is a bizarre choice for this role," Senate Finance Committee Chair Ron Wyden, D-Ore., said in a statement Wednesday.

"What's most concerning is that Mr. Long left office and jumped into the scam-plagued industry involving the Employee Retention Tax Credit," he said.

The employee retention credit was a pandemic-era tax break designed to support small businesses impacted by shutdowns. However, the IRS has denied billions in improper filings after companies pressured businesses to amend payroll returns to claim the tax break.

The Trump transition team didn't respond to CNBC's request for comment.

Sen. Mike Crapo, R-Idaho, lead Republican on the Senate Finance Committee, on Thursday voiced support for Long.

"The IRS has experienced myriad problems in recent years," including privacy and security of taxpayer information, inefficiency and "an oversized emphasis" on enforcement, he said in a statement.

"Protecting taxpayers and addressing an ever-encroaching IRS is a top priority, and I look forward to learning more about Mr. Long's vision for the agency," Crapo said.