Obamacare is the nickname for the Affordable Care Act, a federal law enacted in March 2010 that created a government-run Marketplace where you can buy health insurance, required insurers to cover people regardless of medical history, and set up income-based subsidies to help pay premiums.1HHS.gov. About the Affordable Care Act (ACA) If you’re trying to understand what Obamacare is and how it works in practical terms, the short version is this: you shop for a standardized plan through HealthCare.gov or your state’s exchange, you may qualify for help paying for it based on your income, and the plan you buy has to cover a defined set of benefits no matter what your health history looks like. For 2026, the financial help is meaningfully less generous than it was from 2021 through 2025, so the details matter more than they did a year ago.
What Obamacare Actually Is
The Affordable Care Act reshaped the individual health insurance market. Before the law, insurers in that market could turn you down, charge you more, or exclude specific conditions based on your health history. The ACA ended those practices. Insurers now have to accept every applicant during open enrollment and qualifying special enrollment periods, and they can’t charge you more because of your health status, gender, or occupation.1HHS.gov. About the Affordable Care Act (ACA) The only factors that can legally move your premium are your age, where you live, tobacco use, and how many people are on the plan.
Coverage is sold through the Health Insurance Marketplace, sometimes called the Exchange. Most states use the federal platform at HealthCare.gov, and some run their own state-based exchanges. Every plan sold through the Marketplace covers the same core set of benefits, so the real differences come down to how much you pay in monthly premiums versus how much you pay when you actually use care.
These protections apply to all ACA-compliant plans, whether you buy them on the Marketplace or directly from an insurer. Short-term plans and health care sharing ministries don’t have to follow these rules, which is why they can look cheaper but leave you exposed if you have ongoing health needs.
What Every Marketplace Plan Must Cover
Every Marketplace plan covers the same ten categories of essential health benefits: outpatient care, emergency services, hospitalization, maternity and newborn care, mental health and substance use treatment, prescription drugs, rehabilitative services, lab services, preventive and wellness services, and pediatric services including dental and vision for children under 19.2Centers for Medicare and Medicaid Services. Information on Essential Health Benefits (EHB) Benchmark Plans Mental health and substance use services have to be covered on the same terms as physical health care, and insurers can’t require prior authorization for emergency care.
Preventive services get an extra layer of protection. Immunizations, cancer screenings, blood pressure checks, and annual wellness visits are covered with no copay, coinsurance, or deductible when you use an in-network provider.3HealthCare.gov. Preventive Health Services Go out of network for a screening and you may owe the full bill.
One gap catches people off guard. Dental and vision for kids are essential benefits; adult dental and vision are not.4HealthCare.gov. Dental Coverage in the Marketplace Some Marketplace health plans include basic adult dental, many don’t, and you can buy a standalone dental plan through the Marketplace if you need it.
How Plans Are Organized
Plans are sorted into four metal tiers based on how costs are split between you and the insurer.5HealthCare.gov. Health Plan Categories: Bronze, Silver, Gold, and Platinum Bronze plans cover about 60% of costs, with the lowest premiums and the highest out-of-pocket charges. Silver plans cover about 70%, and they’re the only tier that qualifies for extra cost-sharing help if your income is low enough. Gold plans cover about 80%. Platinum plans cover about 90%, with the highest premiums but very low costs when you use care. Platinum isn’t available everywhere.
People under 30, or anyone with a hardship or affordability exemption, can also buy a Catastrophic plan.6HealthCare.gov. Catastrophic Health Plans Premiums are very low and deductibles very high; the plan covers three primary care visits a year and preventive services at no cost, but you pay for almost everything else until you hit the deductible. If you’re over 30, you can qualify when the cheapest Marketplace plan in your area would cost more than 8.05% of your income in 2026.
Each plan also uses a network structure (HMO, PPO, EPO, or POS) that decides which doctors you can see and what happens if you go outside the network.7HealthCare.gov. Health Insurance Plan and Network Types: HMOs, PPOs, and More HMOs and EPOs generally don’t cover out-of-network care except for emergencies. PPOs and POS plans do, at a higher cost. Before you enroll, check whether your current doctors and medications are actually in the plan’s network and formulary. A cheap Bronze PPO can end up costing more than a mid-range Silver HMO if your doctors aren’t in the PPO’s network.
How Costs Work
Four cost-sharing pieces determine what you actually spend in a year:
- Premium: your monthly payment to keep coverage active, whether or not you use any care.
- Deductible: what you pay out of pocket before the plan starts covering most services. Preventive care is covered even before you meet it.
- Copay or coinsurance: after the deductible, you share costs with the insurer. A copay is a flat fee, like $30 for a doctor visit. Coinsurance is a percentage, like 20% of a hospital bill.
- Out-of-pocket maximum: the most you can be required to pay in a plan year. Once you hit it, the insurer covers 100% of covered services for the rest of the year.
For 2026, the out-of-pocket maximum can’t exceed $10,600 for an individual or $21,200 for a family.8HealthCare.gov. Out-of-Pocket Maximum/Limit The cap applies to in-network covered services only. Out-of-network charges and anything your plan doesn’t cover don’t count toward it.
The tradeoff between tiers is simple. Bronze keeps monthly costs low but hits hard when you use care. Gold flips the equation: higher premiums, much lower cost-sharing each time you see a doctor. If you’re healthy and rarely go in, Bronze may win. If you have a chronic condition or expect real medical expenses, Gold often saves money overall.
Who Can Enroll
To buy a Marketplace plan, you have to live in the United States, be a U.S. citizen or lawfully present immigrant, and not be incarcerated.9USA.gov. How to Get Insurance Through the ACA Health Insurance Marketplace Undocumented immigrants cannot purchase Marketplace coverage. You apply through the Marketplace in the state where you live.
Having other qualifying coverage changes your options. If your employer offers a plan that meets federal standards, you generally can’t receive Marketplace subsidies. For 2026, employer coverage counts as “affordable” when your share of the premium for self-only coverage is no more than 9.96% of household income.10Internal Revenue Service. Rev. Proc. 2025-25 If it costs more than that, you can shop on the Marketplace and potentially get financial help.
Financial Help in 2026
Two forms of help exist: premium tax credits that lower your monthly bill, and cost-sharing reductions that shrink your deductibles and copays. Both depend on your household income relative to the federal poverty level.
Premium Tax Credits
Premium tax credits go to households with incomes between 100% and 400% of the federal poverty level.11Internal Revenue Service. Eligibility for the Premium Tax Credit For 2026, that’s $15,960 to $63,840 for a single person in the continental U.S., and $33,000 to $132,000 for a family of four.12HHS.gov. 2026 Poverty Guidelines The credit uses a sliding scale tied to a benchmark Silver plan: the lower your income, the less you’re expected to contribute.
This changed sharply for 2026. From 2021 through 2025, Congress temporarily removed the 400% FPL cap and lowered the percentage of income everyone had to pay. Those enhanced credits expired on January 1, 2026, and Congress has not extended them.13Congress.gov. Enhanced Premium Tax Credit and 2026 Exchange Premiums A household at 200% of the poverty level that paid about 2% of income toward a benchmark plan in 2025 now pays about 6.6% in 2026. Households above 400% FPL who previously received credits no longer qualify at all.
You can take the credit in advance, applied straight to your monthly premium, or claim it when you file your tax return. Eligibility is based on modified adjusted gross income, which includes wages, Social Security benefits, and tax-exempt interest.14HealthCare.gov. Federal Poverty Level (FPL)
Cost-Sharing Reductions
If your income falls between 100% and 250% of the FPL, a second layer of savings reduces your deductibles, copays, and coinsurance. The catch: you have to enroll in a Silver plan to get them.15HealthCare.gov. Cost-Sharing Reductions Pick Bronze or Gold and you keep your premium tax credit but lose cost-sharing reductions entirely. At around 150% of FPL, a Silver plan with cost-sharing reductions can cover roughly 94% of medical costs instead of the standard 70%. It’s one of the most valuable and most overlooked benefits in the Marketplace.
Medicaid and the Coverage Gap
The ACA also expanded Medicaid to cover adults with incomes up to 138% of the FPL, but the Supreme Court made expansion optional for each state. As of 2026, 40 states and the District of Columbia have adopted expansion.16HealthCare.gov. Medicaid Expansion and What It Means for You In those states, if your income is below 138% of FPL (about $22,025 for an individual in 2026), you’ll likely qualify for Medicaid rather than a Marketplace plan.
In the 10 states that haven’t expanded, a coverage gap exists. Adults without children who earn below 100% FPL often don’t qualify for Medicaid under the old rules, and they also don’t qualify for Marketplace premium tax credits because those start at 100% FPL. If you fall into that gap, your options are limited to unsubsidized Marketplace plans, community health centers, or state-specific assistance.
When to Sign Up
Open enrollment for a Marketplace plan runs from November 1 through January 15.17HealthCare.gov. When Can You Get Health Insurance Enroll by December 15 for coverage starting January 1. Enroll between December 16 and January 15 and coverage starts February 1. Some state-based exchanges use slightly different deadlines, so check your state if you’re not on HealthCare.gov.
If you already have a Marketplace plan and do nothing during open enrollment, you’ll be automatically re-enrolled in the same plan, or a similar one if yours is no longer offered.18HealthCare.gov. Automatic Re-Enrollment Keeps You Covered Convenient, but risky. Your subsidy amount and plan pricing change every year, especially into 2026. Logging in and actively comparing plans can save real money. To cancel entirely and avoid auto-renewal, do it by December 15.
Outside open enrollment, you can only sign up or switch plans after a qualifying life event, and you generally have 60 days from the event.19HealthCare.gov. Getting Health Coverage Outside Open Enrollment Qualifying events include losing existing coverage, marriage or divorce, having or adopting a child, moving to a new ZIP code or county, becoming a U.S. citizen or gaining lawful immigration status, and being released from incarceration. Voluntarily dropping a plan or missing a premium payment doesn’t count. If you lose Medicaid or CHIP, you get 90 days instead of 60.
Reconciling Your Subsidy at Tax Time
If you take advance premium tax credits during the year, you have to file Form 8962 with your tax return to reconcile what you received with what you actually qualify for based on your final income.20Internal Revenue Service. Reconciling Your Advance Payments of the Premium Tax Credit Income higher than you estimated means you may owe some of the credit back. Income lower means you get the extra as part of your refund.
Skipping this step matters. If you don’t file Form 8962, you become ineligible for advance premium tax credits and cost-sharing reductions the following year. Your insurer will send you Form 1095-A each January, and the Marketplace uses it to complete the reconciliation. Keep the form.
What About the Individual Mandate?
The federal penalty for going without health insurance was reduced to $0 starting in 2019, so at the federal level there’s no fine for staying uninsured. Five states and the District of Columbia keep their own mandates with tax penalties: California, Massachusetts, New Jersey, Rhode Island, and the District of Columbia. Vermont requires residents to report coverage but currently imposes no fine.
State penalties are generally calculated as the greater of a flat dollar amount per adult or a percentage of household income, capped at the cost of an average Bronze plan. If you live in one of those states and go without qualifying coverage, the penalty shows up on your state income tax return. Exemptions are available for financial hardship, short coverage gaps of less than three consecutive months, and membership in certain religious groups that object to insurance.21U.S. Department of the Treasury. Treasury ACA Exemption Fact Sheet