Medicare premiums are set to rise a modest amount next year, but still cut into any Social Security gains. The basic monthly premium will increase $3.90, from $144.60 a month to $148.50.

The Centers for Medicare and Medicaid Services (CMS) announced the premium and other Medicare cost increases on November 6, 2020. The hike could have been much worse due to rising costs during the coronavirus pandemic, but the bipartisan budget bill passed in October capped the increase. While the majority of beneficiaries will pay the added amount, a “hold harmless” rule prevents Medicare recipients’ premiums from increasing more than Social Security benefits, which are going up only 1.3 percent in 2021. This “hold harmless” provision does not apply to Medicare beneficiaries who are enrolled in Medicare but who are not yet receiving Social Security, new Medicare beneficiaries, seniors earning more than $88,000 a year, and “dual eligibles” who get both Medicare and Medicaid benefits.

Meanwhile, the Part B deductible will rise from $198 to $203 in 2021, while the Part A deductible will go up by $76, to $1,484. For beneficiaries receiving skilled care in a nursing home, Medicare’s coinsurance for days 21-100 will increase from $176 to $185.50. Medicare coverage ends after day 100.

Here are all the new Medicare payment figures:
•    Part B premium: $148.50 (was $144.60)
•    Part B deductible: $203 (was $198)
•    Part A deductible: $1,484 (was $1,408)
•    Co-payment for hospital stay days 61-90: $371/day (was $352)
•    Co-payment for hospital stay days 91 and beyond: $742/day (was $704)
•    Skilled nursing facility co-payment, days 21-100: $185.50/day (was $176)

So-called “Medigap” policies can cover some of these costs.

Premiums for higher-income beneficiaries ($88,000 and above) are as follows:

• Individuals with annual incomes between $88,000 and $111,000 and married couples with annual incomes between $176,000 and $222,000 will pay a monthly premium of $207.90.
• Individuals with annual incomes between $111,000 and $138,000 and married couples with annual incomes between $222,000 and $276,000 will pay a monthly premium of $297.
• Individuals with annual incomes between $138,000 and $165,000 and married couples with annual incomes between $276,000 and $330,000 will pay a monthly premium of $386.10.
• Individuals with annual incomes above $165,000 and less than $500,000 and married couples with annual incomes above $330,000 and less than $750,000 will pay a monthly premium of $475.20.
• Individuals with annual incomes above $500,000 and married couples with annual incomes above $750,000 will pay a monthly premium of $504.90.

Rates differ for beneficiaries who are married but file a separate tax return from their spouse. Those with incomes greater than $88,000 and less than $412,000 will pay a monthly premium of $475.20. Those with incomes greater than $412,000 will pay a monthly premium of $504.90.

The Social Security Administration uses the income reported two years ago to determine a Part B beneficiary’s premium. So the income reported on a beneficiary’s 2019 tax return is used to determine whether the beneficiary must pay a higher monthly Part B premium in 2021. Income is calculated by taking a beneficiary’s adjusted gross income and adding back in some normally excluded income, such as tax-exempt interest, U.S. savings bond interest used to pay tuition, and certain income from foreign sources. This is called modified adjusted gross income (MAGI). If a beneficiary’s MAGI decreased significantly in the past two years, she may request that information from more recent years be used to calculate the premium. You can also request to reverse a surcharge if your income changes.

Those who enroll in Medicare Advantage plans may have different cost-sharing arrangements. CMS estimates that the Medicare Advantage average monthly premium will decrease by 11 percent in 2021, from an average of $23.63 in 2020 to $21 in 2021.