More than 50 million Americans 65 or older received Medicare benefits in 2018, and the number has been steadily on the rise. As more of the baby boomer generation reaches the 65-year-old eligibility age for Medicare, the healthcare program has been increasingly crucial in providing financial support for healthcare costs for a substantial fraction of the American population. Yet with more recipients comes more expenses for the program, and that's part of why most of those who get Medicare benefits will pay more for the privilege in 2019.

The Centers for Medicare & Medicaid Services recently announced that the base monthly premiums for Medicare Part B, which covers doctor visits and other outpatient care expenses, will rise by $1.50 per month in 2019, coming in at $135.50. As you can see below, the move comes after participants got a brief reprieve last year following large increases in 2016 and 2017.

Line graph of premiums for Medicare Part B.

Data source: Centers for Medicare & Medicaid Services. Chart by author.

By contrast, most Americans don't pay premiums for Medicare Part A, which covers hospital costs and other inpatient healthcare expenses. Instead, those who visit hospitals during the year have to pay a deductible, and that amount will rise by $24 to $1,364 in 2019. In addition, for stays of 61 to 90 days, Medicare participants have to contribute to the cost through a daily coinsurance payment. That amount will rise modestly in 2019 as well, up $6 to $341 per day.

The aging population will make Medicare even bigger over time, with some projections suggesting that the number of enrollees in the program could approach 90 million within the next 20 years. That'll make it even more important for policymakers to keep looking for ways to keep healthcare costs in line, as rising demand from older Americans entering a stage in their lives when health issues typically become increasingly numerous could threaten to put an insurmountable burden on the healthcare system. For now, although those living on fixed incomes won't appreciate paying more for Medicare, they'll be glad that the price hike isn't even larger.

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