The standard Medicare Part B premium will rise to $174.70 a month in 2024, up $9.80 from this year, while the annual Part B deductible will increase to $240, the Centers for Medicare & Medicaid Services announced Thursday. The 5.9% premium increase lands on the same day the Social Security Administration announced a 3.2% cost-of-living adjustment for 2024, creating a direct interaction between higher retirement benefits and higher health-insurance deductions for millions of beneficiaries.

CMS attributed the Part B increase primarily to projected growth in health-care spending and, to a lesser degree, changes connected to Medicare’s remedy for underpayments involving 340B-acquired drugs. For most beneficiaries, the Part B premium is deducted directly from Social Security checks, so the two announcements must be considered together rather than as separate household-budget changes.

The premium rises faster than the COLA

Social Security said benefits for more than 71 million Americans will increase 3.2% in 2024. The agency’s October 12 announcement said the average retirement benefit will rise by more than $50 per month beginning in January. The increase is substantially smaller than the 8.7% adjustment beneficiaries received for 2023 as inflation has moderated.

For beneficiaries enrolled in Part B, however, the higher Medicare premium absorbs part of that increase. A person paying the standard premium will see the monthly deduction rise from $164.90 to $174.70. The precise net effect varies with each person’s Social Security benefit, income-related Medicare adjustment and other deductions.

The Social Security Administration’s 2024 fact sheet confirms that the COLA is tied to the third-quarter change in the Consumer Price Index for Urban Wage Earners and Clerical Workers. That indexing mechanism protects purchasing power imperfectly because individual retirees may experience medical, housing or food costs differently from the broad index.

Part B finances physician and outpatient care

Medicare Part B covers physician services, outpatient hospital care, durable medical equipment and certain other medical services. Unlike Part A hospital coverage for most beneficiaries, Part B is financed partly through premiums paid by enrollees and partly through federal general revenues. The premium is recalculated each year based on expected program costs.

CMS also set income-related premium tiers for higher-income beneficiaries. Roughly 8% of people with Part B pay more than the standard amount based on modified adjusted gross income. Those surcharges mean the 2024 premium change is not uniform across the Medicare population.

The annual deductible will rise from $226 to $240. Once that deductible is met, beneficiaries generally owe 20% coinsurance for many Part B services unless they have supplemental coverage or another payer.

Other Medicare premiums are moving differently

The Part B increase contrasts with the outlook for Medicare Advantage and Part D prescription-drug coverage. CMS said in a September 26 release that average Medicare Advantage and Part D premiums, benefits and plan choices are expected to remain broadly stable in 2024.

For stand-alone and other Part D coverage, CMS earlier projected that the average total beneficiary premium would decline 1.8%, from $56.49 in 2023 to $55.50 in 2024. The agency’s Part D projection linked that stability partly to Inflation Reduction Act provisions limiting growth in the base beneficiary premium and changing prescription-drug cost sharing.

Those changes include continued $35 monthly caps on covered insulin products and no cost sharing for recommended adult vaccines under Part D. They do not eliminate the broader pressure of medical-cost growth that drives Part B spending.

Long-term Medicare costs remain a structural issue

The 2023 Social Security and Medicare trustees summary projects that Medicare spending will rise from 3.9% of gross domestic product in 2023 to 6.0% by 2045. The trustees’ report attributes much of the growth to an aging population and rising per-beneficiary health spending.

That long-term trend helps explain why annual premium announcements matter beyond a single year. Part B premiums are not simply prices set administratively; they are one financing mechanism for a program whose costs are linked to utilization, provider payments, drug spending and demographic change.

The 2024 numbers therefore tell two stories at once. Inflation has slowed enough to reduce the Social Security COLA sharply from last year’s unusually large adjustment, while health-care costs continue to push the Medicare Part B premium higher. For retirees living largely on fixed income, the difference between those rates will determine how much of January’s nominal benefit increase becomes additional spendable income.

Open enrollment begins this month, giving beneficiaries an opportunity to compare Medicare Advantage and Part D options for 2024. The standard Part B premium, however, is a national baseline. At $174.70 a month, it will be one of the most consequential fixed deductions from Social Security benefits in the coming year.