The Affordable Care Act (ACA), commonly known as Obamacare, is an American health-care law signed in 2010. It created insurance marketplaces where people can compare and buy health insurance, and expanded Medicaid to cover more low-income Americans.
Since the introduction of enhanced tax credits during the covid pandemic, enrolment in the ACA marketplaces has doubled. As of late 2025, more than 24m people buy their insurance through the marketplaces. Three-quarters of them live in states Donald Trump won in the 2024 election.
The enhanced subsidies are expensive. Extending them until 2035 would cost $350bn, according to the Congressional Budget Office. The Democratic architects of the extra subsidies made them temporary. In late 2025 Republicans remained divided over whether to extend them; the Congressional Budget Office estimated that letting them expire would probably cause 3.5m people to become uninsured by 2027.
With the end of the pandemic-era subsidies, the average premium rose by 114%, according to KFF, a health-research outfit. In the initial sign-up period just 5% fewer people enrolled—a smaller drop than many expected—but the number of uninsured is expected to rise as auto-enrollees notice bigger bills and healthier people opt out, worsening the risk pool.
The ACA has always blocked federal subsidies from paying for abortion. Some states require marketplace plans to cover the procedure, leading to complicated accounting in which abortion care is paid for by a fund kept separate from federal money.
It's always darkest just before it gets pitch black.