“I want to thank Commissioner Rettig for his tireless service to the American people across two administrations, and his leadership of the IRS during the difficult and unique challenges posed by COVID-19. I am grateful to him for his partnership and efforts to ensure taxpayers had the resources they needed to make it through the pandemic,” Treasury Secretary Janet Yellen said in a written statement. “Deputy Commissioner O’Donnell has dedicated his career to serving American taxpayers through every level of the agency. His commitment to improving the experience of the American taxpayer will guide his and the agency’s work as they continue their efforts to propel the IRS forward during a critical period of modernization. Now more than ever, the IRS has the momentum to transform with service, technology and workforce improvements that will make it a world-class agency to meet the needs of the American people.”

President Joe Biden is in the process of finding a new IRS commissioner to nominate. Bloomberg reported last month that the Biden administration wants someone with deep management and business experience to lead the agency.