On Trump's first day as president, Musk already had his own White House email address. Billionaire Musk, who is about to become the head of the Department of Government Effectiveness (DOGE), said his emails are already available in the internal search function of the President's Executive Office, a source said. The source also showed a screenshot showing Musk's new email address with the suffix EOP, which stands for the President's Executive Office. "This seems to confirm that he will have an office in the Eisenhower Executive Office Building," the source said. A source familiar with Musk's ties to the Trump administration also said that Musk will have an office in the Eisenhower Executive Office Building. But it is unclear how often the billionaire will use the office space.