Dear Savvy Senior:

I know there will be a small cost-of-­living increase in Social Security benefits next year, but what about Medicare? What will the Medicare Part B monthly premiums be in 2021, and when do the surcharges kick in for higher-­income beneficiaries? — Inquiring Senior

Dear Inquiring: The Centers for Medicare and Medicaid Services recently announced their cost adjustments for 2021, and the increases for premiums and out-of-pocket costs for most beneficiaries will be modest. But if you’re a high earner, you’ll pay more. Here’s what you can expect starting in January.

Medicare Part B

While Medicare Part A, which pays for hospital care, is premium-free for most beneficiaries, Part B, which covers doctor visits and outpatient services, does have a monthly premium. Starting in 2021, the standard monthly Part B premium will be $148.50, up from $144.60 in 2020. That $3.90 bump represents a 2.7% increase, which is more than double the most recent Social Security cost-of-living adjustment, which was 1.3%.

But if you’re a high-earning beneficiary, which makes up about 7% of all Medicare recipients, you’ll have to pay more. Medicare surcharges for high earners are based on adjusted gross income from two years earlier, which means that 2021 Part B premiums are determined by 2019 annual income.

So, if your 2019 income was above $88,000 up to $111,000 ($176,000 up to $222,000 for married couples filing jointly), your 2021 Part B monthly premium will be $207.90, up from $202.40 in 2020.

Monthly premiums for singles with an income between $111,000 and $138,000 ($222,000 and $276,000 for joint filers) will rise to $297 from $289.20. Individuals earning above $138,000 up to $165,000 ($276,000 to $330,000 for joint filers) will see their monthly premium increase to $386.10 from $376.

Those with incomes above $165,000 up to $500,000 ($320,000 to $750,000 for joint filers), you’ll pay $475.20 per month in 2021. And single filers with income of $500,000 or more ($750,000 or more for joint filers) will pay $504.90 per month next year.

Medicare Part D

If you have a Medicare (Part D) prescription drug plan, the average premium in 2021 will be about $30 per month for most beneficiaries. But again, for high earners with annual incomes above $88,000 ($176,000 for joint filers), you’ll pay a $12.30 to $77.10 monthly surcharge on top of your regular Part D premiums.

How to contest income

Beneficiaries who fall into any of the high-income categories and have experienced certain life-changing events that have reduced their income since 2019, such as retirement, divorce or the death of a spouse, can contest the surcharge. For more information on how to do this, see “Medicare Premiums: Rules for Higher-­Income Beneficiaries” at SSA.gov/benefits/medicare/medicare-premiums.html.

Other increases

In addition to the Part B and Part D premium increases, there are other cost increases you should be aware of. For example, the annual deductible for Medicare Part B will see a bump to $203 from $198 in 2021. The deductible for Medicare Part A, which covers hospital services, will increase from $1,408 in 2020 to $1,484 in 2021. There are no surcharges on Medicare deductibles for high earners.

For more information on all the Medicare costs for 2021, visit Medicare.gov and click on “2021 Medicare Costs,” or call 800-633-4227.

Jim Miller is a contributor to NBC-TV’s “Today” program and author of “The Savvy Senior.” Send your questions to Savvy Senior, P.O. Box 5443, Norman, OK 73070; or visit savvysenior.org.