Healthcare reform in the United States refers primarily to the Affordable Care Act (ACA), signed into law in 2010, along with subsequent legislation that has reshaped how Americans get and pay for health insurance. The core goal has been to reduce the number of uninsured people, make coverage more affordable, and set minimum standards for what insurance actually covers. As of 2024, the uninsured rate sits at 8.2% of all Americans (about 27.2 million people), down from 9.7% in 2020.
What the Affordable Care Act Changed
Before the ACA, insurers could deny you coverage or charge you more based on your medical history. That practice ended for most plans. Insurers now cannot refuse to cover you or refuse to pay for treatment of a condition you already had when you signed up. The only exception is “grandfathered” plans that existed before the law took effect and haven’t significantly changed their terms.
The law also created insurance marketplaces, the most visible being HealthCare.gov, where individuals and families can compare and purchase plans. During the 2025 open enrollment period, 24.3 million people selected or were automatically re-enrolled in coverage through these exchanges. That number has grown steadily since the marketplaces launched in 2014.
Young adults gained the right to stay on a parent’s health plan until they turn 26, regardless of whether they’re married, have children, are in school, or live at home. If you’re on a parent’s marketplace plan specifically, coverage extends through December 31 of the year you turn 26.
Financial Help for Coverage
The ACA introduced premium tax credits to lower monthly insurance costs. These subsidies are available to households earning between 100% and 400% of the federal poverty level. For a single person in 2024, that range is roughly $15,000 to $60,000 in annual income, though the exact numbers shift each year with updated poverty guidelines.
During 2021 and 2022, Congress temporarily removed the 400% income cap, meaning even higher earners could qualify for some level of assistance. That expansion was part of the American Rescue Plan and was later extended. If your income falls below 100% of the poverty level, you may still qualify depending on your state’s Medicaid rules.
Medicaid Expansion
One of the ACA’s most significant provisions extended Medicaid eligibility to all adults under 65 earning below 138% of the federal poverty level. Before this change, many states only covered very low-income parents and excluded childless adults entirely, no matter how little they earned.
As of March 2023, 40 states and Washington, D.C. have adopted the expansion. The remaining states have not, which creates a coverage gap: in those states, some adults earn too much for traditional Medicaid but too little to qualify for marketplace subsidies. The federal government covers 90% of the cost for newly eligible adults in expansion states, a higher share than it pays for the traditional Medicaid population.
What Insurance Plans Must Cover
All marketplace plans and small-group insurance plans are required to cover ten categories of essential health benefits:
- Outpatient care (doctor visits and services you receive without being admitted to a hospital)
- Emergency services
- Hospitalization
- Maternity and newborn care
- Mental health and substance use treatment
- Prescription drugs
- Rehabilitative services and devices
- Lab tests
- Preventive care, wellness visits, and chronic disease management
- Pediatric services, including dental and vision for children
Before the ACA, many individual-market plans excluded categories like maternity care or mental health treatment. The law established a floor: no matter which marketplace plan you choose, it must include all ten categories.
Preventive Care at No Extra Cost
A practical change many people encounter is that a wide range of preventive services must be covered with zero copay, coinsurance, or deductible. This includes blood pressure, diabetes, and cholesterol screenings. Breast and colon cancer screenings. Routine vaccines for diseases like measles, polio, meningitis, flu, and pneumonia. Counseling for quitting smoking, weight management, depression, and alcohol use.
Children from birth to age 21 are covered for regular well-child visits, vision and hearing screenings, developmental assessments, immunizations, and obesity screening. Pregnant individuals receive counseling, screening, and vaccines related to healthy pregnancies. The requirement applies to all non-grandfathered plans, meaning most people with employer coverage benefit from these rules too, not just those who buy through the marketplace.
Recent Reforms Beyond the ACA
Healthcare reform didn’t stop with the ACA. The Inflation Reduction Act, signed in 2022, made several changes focused on prescription drug costs for people on Medicare. The most widely discussed provision allows Medicare to negotiate prices directly with drug manufacturers for the first time. Negotiations began in 2023 with a list of 10 high-cost drugs, and the resulting prices took effect in 2026. The program scales up over time: 15 drugs in 2027 and 2028, then 20 drugs per year starting in 2029.
The same law capped insulin costs at $35 per month for Medicare enrollees, both for pharmacy prescriptions and insulin administered in a clinical setting. It also eliminated out-of-pocket costs for certain vaccines covered under Medicare’s prescription drug benefit, a category that previously required cost sharing from patients.
How the Uninsured Rate Has Shifted
The clearest measure of healthcare reform’s impact is the uninsured rate. In 2010, before the ACA’s major provisions took effect, roughly 16% of Americans lacked coverage. By 2024, that figure dropped to 8.2%. Among working-age adults (18 to 64), who are the primary target of reform since older adults have Medicare and children often qualify for Medicaid or CHIP, 11.6% were uninsured in 2024.
The remaining uninsured population includes people in states that haven’t expanded Medicaid, undocumented immigrants who are ineligible for marketplace coverage, and people who are eligible for assistance but haven’t enrolled. Cost remains a barrier for some, even with subsidies, particularly in areas with limited insurer competition where premiums run higher.
What Reform Looks Like Day to Day
If you get insurance through your job, healthcare reform mostly shows up as preventive visits with no copay, coverage for dependents under 26, and no lifetime dollar limits on what your plan will pay. If you buy your own coverage, you shop through the marketplace, potentially receive a tax credit that lowers your monthly premium, and choose from plans that all meet the same minimum coverage standards.
If your income is low enough and you live in an expansion state, you likely qualify for Medicaid with little or no premium. If you’re on Medicare and take expensive medications, you may see lower drug costs as negotiated prices phase in over the next several years. The system is still fragmented, with coverage varying by state, employer, and income level, but the structural changes from the past 15 years have made it significantly harder to be locked out of coverage entirely.