The total includes more than 137,000 new enrollees for the week from Jan. 17 through Jan. 23. The federal exchange that serves 37 states through the website, HealthCare.gov.
Not included are enrollees who have signed up through 13 state-run exchanges.
On Tuesday, the administration said that 9.5 million consumers had selected 2015 plans through both the federal and state marketplaces by mid-January.
Open enrollment for 2015 began on Nov. 15 and runs through Feb. 15.