What Is Obamacare (the ACA)?

On this page

• What the ACA does
• How Obamacare coverage works
• When you can sign up
• Who qualifies for help
• Is there still a penalty for not having insurance?
• What’s changed recently
• Getting the most from an ACA plan
• Frequently asked questions

What the ACA does

The Affordable Care Act was signed in March 2010, and its marketplaces opened for 2014 coverage. Its main pieces:

• Protections for people with health conditions. Plans can’t deny you, charge more or exclude care because of a pre-existing condition, whether that’s cancer, diabetes or anything else.
• Essential health benefits. Marketplace and small-business plans cover 10 categories of care, including hospital stays, prescriptions, maternity care and mental health care.
• Free preventive care. Recommended screenings, checkups and vaccines cost nothing in network. In 2025, the Supreme Court upheld the rule behind this coverage.
• Limits on what you pay. Plans have a yearly out-of-pocket maximum, capped at $10,600 for one person in 2026, and can’t set lifetime or annual dollar limits on essential benefits.
• Coverage for young adults. Children can stay on a parent’s plan until 26.
• Marketplaces and subsidies. HealthCare.gov and state exchanges sell plans, with premium tax credits to lower the cost.
• Medicaid expansion for adults with low incomes, in states that choose it.
• An employer mandate. Companies with 50 or more full-time workers must offer affordable coverage or may owe a penalty.

How Obamacare coverage works

You apply on HealthCare.gov or your state’s marketplace with information about your household and your expected income for the year. The marketplace tells you whether you qualify for Medicaid or CHIP, a premium tax credit, or cost-sharing reductions, and shows you plans in your area.

Plans are grouped by metal level: bronze, silver, gold and platinum, from lowest premium to lowest out-of-pocket costs. See the difference between bronze, silver, gold and platinum plans and how much coverage health insurance actually offers.

You can take the tax credit in advance to lower your monthly bill, or claim it on your tax return. If you take it in advance, your final credit is settled at tax time based on your actual income, so reporting your income accurately matters. Starting with 2026 coverage, there’s no cap on how much extra credit you may have to repay.

When you can sign up

You can enroll during the yearly open enrollment period. For 2027 coverage, it runs November 1, 2026, to January 15, 2027, on HealthCare.gov. Sign up by December 15 for coverage that starts January 1. Some states run longer.

Outside that window, you need a special enrollment period, usually 60 days after events like having a baby, getting married or divorced, moving, or losing job-based coverage. Medicaid and CHIP accept applications any time.

You can also buy an ACA plan directly from an insurer, but tax credits are only available through the marketplace.

Who qualifies for help

Income (share of federal poverty level)	Help available
Up to 138% in expansion states	Medicaid for most adults
100% to 250%	Premium tax credit plus cost-sharing reductions on silver plans
250% to 400%	Premium tax credit
Above 400%	No tax credit; full price

If you have affordable coverage through a job, or qualify for Medicaid or Medicare, you generally can’t get a marketplace tax credit.

Is there still a penalty for not having insurance?

Not at the federal level. Congress set the penalty to $0 starting in 2019. California, Massachusetts, New Jersey, Rhode Island and Washington, DC, have their own penalties. Even without a penalty, going uninsured is a big financial risk; see what’s the worst that can happen if I get sick without health insurance.

What’s changed recently

• Larger subsidies expired. The enhanced premium tax credits that ran from 2021 through 2025 ended. The House passed a three-year extension in January 2026, but the Senate hasn’t, so credits follow the original rules again.
• Premiums rose. Benchmark prices went up 26% on average for 2026, and insurers have asked for a median increase of about 15% for 2027.
• The 2025 tax law. It removed the cap on repaying excess tax credits, limits tax credits for many lawfully present immigrants starting in 2027, and adds Medicaid work requirements for many adults starting in 2027.

Getting the most from an ACA plan

Compare several insurers before you choose; here’s how many plans to look at. If cost is the main worry, see the cheapest ways to get health insurance and health insurance discounts.

See ACA plans and prices for your area: compare quotes by ZIP code.

Frequently asked questions

Is Obamacare the same as the ACA?

Yes. “Obamacare” is a nickname for the Affordable Care Act. Plans sold on HealthCare.gov and state marketplaces are ACA plans.

Is Obamacare free?

Not usually, though some low-income enrollees pay little or nothing after the tax credit, and Medicaid is free or nearly free in most states.

Can I get Obamacare if my job offers insurance?

You can buy a plan, but you usually won’t get a tax credit if the job-based plan is affordable, meaning your share for self-only coverage is under 9.96% of household income in 2026 (10.22% in 2027). See can I get marketplace coverage if my employer offers it.

Does Obamacare cover pre-existing conditions?

Yes. ACA plans can’t deny coverage or charge more because of your health history.

This article is general information, not legal or insurance advice. ACA rules change often and vary by state, so check HealthCare.gov, your state’s marketplace or a licensed agent for your situation. Last reviewed September 2026.