Stephen Miller, center, sits behind Susie Wiles, left, and U.S. Trade Representative Jamieson Greer at a bilateral meeting at U.N. Headquarters on Sept. 22, 2026 in New York City. —Chip Somodevilla—Getty Images

President Donald Trump on Friday announced Stephen Miller will be the next White House Chief of Staff starting Monday, the most high-profile shift in his Administration in the aftermath of midterm elections on Tuesday in which Republicans lost control of both chambers of Congress.

Susie Wiles, the current White House Chief of Staff and Trump’s longtime political operative, will be reassigned to oversee “the Trump Political Operation,” according to Trump’s Truth Social Post. 

“I want to thank her for her service as Chief of Staff — She has done a great job!” Trump said. 

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Speaking to reporters Friday afternoon, Trump praised Miller as "a great manager" and "very good politically and a very good man."

“Stephen’s been with me from the beginning," he said. "He gets it."

Wiles, 69, was diagnosed with breast cancer earlier this year and underwent six months of chemotherapy while continuing to manage her duties in the White House. In September, Wiles announced that she is cancer-free after the pathology results came back. 

In a statement posted on X, Wiles says it has been “an honor of a lifetime” to serve President Trump in the White House and she is grateful for the people that have worked alongside her.

“While my role may be changing, my commitment to the President and the mission never will,” she said. 

Miller has served as White House Deputy Chief of Staff in Trump’s second term, and is considered to be the central figure of Trump’s immigration agenda, including mass deportations and closing the US-Mexico border. Miller has overseen Trump’s homeland security agenda along with border czar Tom Homan. 

He previously served as senior advisor to the president and director of speechwriting during the first Trump administration. During that period, Miller, along with then White House Strategist Steve Bannon, co-wrote the Muslim ban and encouraged Trump to gradually end the recipients of Deferred Action for Childhood Arrivals, also known as DACA.

Miller’s promotion quickly drew backlash from Democrats in Congress who have vowed to investigate the Trump Administration following a sweeping midterm victory. Rep. Robert Garcia, the likely next chairman of the House Oversight Committee, said in a statement that Stephen Miller should “lawyer up.”

“Oversight Democrats will continue to investigate Miller for his misconduct, and we will fight against his hateful policies in Congress and the courts,” Garcia added.