Record number of Americans have signed up for Obamacare this year, HHS says

A record number of Americans have signed up for health insurance through Affordable Care Act (ACA) marketplaces this year, according to early data published by the Biden administration this week.

More than 15 million people have enrolled in 2024 coverage under the ACA -- often called by its nickname, Obamacare -- as of Dec. 15, which is 33% higher than the roughly 11 million who did so last year.

This figure includes those who have bought insurance through state-based marketplaces or at HealthCare.gov, the website run by the federal government.

The Department of Health & Human Services said it expects more than 19 million to enroll by the deadline of 5 a.m. ET on Jan. 17, 2024 -- about 7 million more people than when President Joe Biden took office. Their coverage will begin on Feb. 1.

On Dec. 15 alone, more than 745,000 enrolled in plans on HealthCare.gov. Health officials said it was the highest number of visitors ever recorded since the portal rolled out in 2013.

"Millions of Americans signing up for health care coverage under the Affordable Care Act is good news. It means more Americans have the peace of mind of knowing that going to the doctor won't empty their bank account," HHS Secretary Xavier Becerra said in a statement. "The Biden-Harris Administration will continue working to expand health care coverage and lower prescription drug costs, so taking care of your health is not a luxury."

HHS did not immediately reply to ABC News' request for comment.

One reason for increased enrollment is likely due to millions of Americans losing Medicaid, a government program that provides health insurance for adults and children with low incomes.

During the COVID-19 pandemic, when the government issued its two emergencies, states were not allowed to delist people so nearly 95 million people received coverage through Medicaid by the end of March 2023, according to nonprofit KFF.

States were also given additional federal funding for the last three years to provide continuous Medicaid coverage, ensuring no one lost health care amid the throes of COVID-19.

When the Biden administration ended both the COVID-19 national emergency and public health emergency on May 11 of this year, states began reviewing their rolls to see if enrollees were still eligible for government-funded health care.

More than 13.3 Medicaid enrollees have been removed as of Dec. 20, according to KFF. The nonprofit believes this is actually an undercount due to lags in state data.

Another reason for the increased enrollment could be the number of people who became uninsured under former President Donald Trump's administration. Gallup data shows that in 2019, 13.7% of adults were without health insurance.

While this is lower than the percentage of Americans that were without health insurance before the ACA, the Trump administration ended cost-sharing reduction, rolled back the individual mandate penalty and cut back on enrollment outreach, according to Gallup.

Trump has vowed to replace the ACA with his own health care plan if elected president again.

Despite the record enrollment, more than 25.6 million non-elderly Americans were uninsured in 2022, according to KFF. HHS says the Biden administration "continues to make increasing coverage a top priority" through provisions in the Inflation Reduction Act that result in savings and a competitive marketplace.

ABC News' Cheyenne Haslett contributed to this report.