There are many things about Medicare you may not know, such as that it was signed into law in 1965 or that it provides coverage for millions of people across the United States.
Medicare is a federally funded healthcare program for people from ages 65 years and those with certain disabilities and illnesses.
Medicare covers both inpatient and outpatient healthcare. It also covers hospice care, some home healthcare, preventive care, and durable medical equipment.
President Lyndon B. Johnson signed Medicare into law in 1965 at the Truman Library in Independence, Missouri. He chose this location to draw attention to the time it had taken Congress to enact this health insurance for older adults after Harry Truman’s proposal more than 20 years earlier.
Before Medicare was signed into law, only a little over 50% of people 65 years and older had any type of hospital insurance. Few among the insured had coverage for surgical and outpatient physicians’ costs. There were also numerous instances when private insurance companies terminated health policies for older adults who were considered high risk.
According to the Centers for Medicare and Medicaid Services (CMS), 68.6 million people were enrolled in Medicare as of March 2025. Of those enrollees, 90.1% were over 65 years old.
The nonprofit KFF notes that in 2024, 32.8 million people enrolled in Medicare Advantage (Part C) plans, accounting for around 54% of the eligible Medicare population.
Even though Medicare does cover much of the healthcare expenses of beneficiaries, out-of-pocket costs are still involved.
Medicare Part A involves a deductible for each benefit period. In 2025, the deductible is $1,676. You are also responsible for daily copayments, depending on how long you are in the hospital.
Medicare Part B also has a deductible, which is annual and set at $257 in 2025. Everyone with Medicare is responsible for paying the Part B monthly premium, which starts at $185. Once you meet the deductible, Medicare covers 80% of the approved costs.
If you have Medicare Advantage, Part D, or Medigap, you may have to pay an additional premium and deductible depending on the plan.
Before 2025, people with a Part D plan would enter the coverage gap or “donut hole” when they reached a certain amount of out-of-pocket costs. In 2024, this amount was $5,030. When you reached the set amount, you would have to pay a higher percentage of your prescription drug costs, up to 100%. You paid this until you met the catastrophic coverage threshold.
In 2024, this threshold was $8,000. Once you reached catastrophic coverage, you paid nothing out of pocket for your prescription drugs for the rest of the year.
The donut hole was eliminated as of January 1, 2025, and replaced by an out-of-pocket spending cap. This cap is $2,000 in 2025 and set to rise to $2,100 in 2026.
Once you reach this set cap, you automatically enter catastrophic coverage and pay nothing for your prescription drugs for the rest of the year.
There are four parts to Medicare. Medicare parts A and B make up Original Medicare.
- Medicare Part A covers:
- inpatient care at hospitals, skilled nursing facilities, and hospice
- some in-home healthcare
- Medicare Part B covers:
- outpatient services from doctors and other healthcare professionals
- some home healthcare
- durable medical equipment
- preventive services
- Medicare Advantage (Part C) covers:
- everything Original Medicare (parts A and B) covers
- additional benefits like vision, dental, hearing, and fitness programs
- Medicare Part D covers prescription drugs
Medicare offers a yearly wellness visit for beneficiaries enrolled in Medicare Part B for more than 12 months.
These yearly wellness visits are not physical exams. They are designed to develop or update a personalized plan based on your current risk factors to help prevent illness and disability.
Original Medicare (parts A and B) doesn’t cover everything, including:
- long-term care
- eye exams for prescription glasses
- massage therapy
- cosmetic surgery
- hearing aids and the exams to fit them
- routine physical exams
- concierge care
- covered items or services that are received from a healthcare professional who has opted out of Medicare
- most dental care
If you have additional health coverage, it may help cover some of these. In addition, Medicare Advantage (Part C) plans often offer additional coverage, like vision, hearing, and dental, that Original Medicare doesn’t.
According to KFF, enrollment in Medicare Advantage has more than doubled since 2010. It is projected to grow from 54% of Medicare beneficiaries in 2024 to 60% by the end of the decade.
There are various reasons for this increase in Medicare Advantage enrollment, including:
- the additional coverage offered
- more plans are becoming available with $0 premiums, other than the Part B premium
- the premiums for stand-alone Part D plans are rising
- the financial security of annual out-of-pocket limits associated with Medicare Advantage plans
In March 2010, President Barack Obama signed the Affordable Care Act (ACA) into law. The aim of the ACA was to make healthcare more affordable.
Medicare was one of the programs affected by the ACA. The ACA made various changes, including:
- phasing out the Part D coverage gap (donut hole)
- providing a free annual wellness exam
- eliminating coinsurance for preventive services
The ACA also made allowances and changes with the aim of sustaining the Medicare program in the future.
Certain Medicare monthly premiums are affected by your income. Part B and Part D premiums can increase depending on your annual income. This is known as the income-related monthly adjustment amount (IRMAA).
IRMAA thresholds are subject to annual changes. In 2025, if you file taxes individually and your annual income is higher than $106,000, you may be subject to a higher Part B premium. If you file as a married couple, your income limit is $212,000.
Medicare is a federal program that provides health coverage to people 65 years and older and those with certain disabilities or illnesses.
President Lyndon B. Johnson signed Medicare into law in 1965. It provides comprehensive coverage for beneficiaries, but it may not cover everything. Certain out-of-pocket costs may also be associated with Medicare coverage.