A Quiet Rule With a Big Job

The hold-harmless provision is written into the Social Security Act. It applies to Part B premiums only, and its logic is simple: your Social Security payment after the Part B deduction cannot fall from one year to the next because of a premium increase. If the premium rises more than your COLA, the government reduces your premium increase to match your COLA, and your net check stays flat.

Why Congress Built a Floor

The rule exists because most retirees cannot easily absorb a smaller check. Without it, a large premium jump in a year with a small or zero COLA would directly cut income for millions of older Americans. The provision guarantees that, at worst, a covered beneficiary’s net payment stays the same. It does not guarantee a raise, which is why many retirees still feel squeezed when premiums rise faster than benefits.

When the Rule Mattered Most

The provision rarely makes headlines because, in most years, COLAs comfortably cover premium increases. It became a major issue in 2016, when there was no COLA at all, and in 2017, when the COLA was just 0.3%. In those years, a large share of beneficiaries were held harmless and paid less than the standard premium, while those not protected paid the full, higher amount. That uneven split is the rule’s hidden cost: when many people are protected, the premium for everyone else can be higher.

The 2027 Math: Why Few People Need the Shield This Time

This year’s numbers are friendly. A 3.6% raise on the average retirement benefit adds about $75 a month, according to SSA. A $6.60 premium increase, if the Trustees’ projection holds, would consume less than a tenth of that. Contrast that with 2026, when a 2.8% COLA added roughly $56 to the average $2,071 benefit and the $17.90 premium increase took nearly a third of it, according to 24/7 Wall St.

The Break-Even Benefit

Here is a useful way to see who could still need protection. Divide the premium increase by the COLA rate, and you get the monthly benefit at which the raise exactly covers the higher premium. For 2027, that is $6.60 divided by 3.6%, or about $183 a month. Anyone whose Social Security benefit is above that level should see a raise larger than the premium increase. In 2026, the same calculation produced about $639, meaning far more people with small benefits relied on the rule.

Who the Rule Leaves Out

AARP reports that about 30% of Part B enrollees are not eligible for hold-harmless protection. According to the Medicare Rights Center, you must have received Social Security benefits in November and December of the prior year and had your Part B premium deducted from those benefits, and you cannot be paying the income-related surcharge. The exclusions explain why some people see bigger premium jumps than their neighbors.

The Higher-Income Gap

People with higher incomes pay an income-related monthly adjustment amount, or IRMAA, on top of the standard premium. About 5.1 million beneficiaries paid IRMAA in 2025, AARP reported. They are not protected by hold-harmless, so their full premium increase passes through. IRMAA is based on modified adjusted gross income from two years earlier, so 2027 surcharges will generally be based on 2025 tax returns. The 2027 brackets had not been announced as of this update.

Beyond Part B: The Other 2027 Costs

Hold-harmless only touches Part B. Other Medicare costs are changing too. Industry reports citing CMS’s 2027 Part D rate announcement say the annual out-of-pocket cap on covered drugs will rise from $2,100 to $2,400, the standard deductible will be $700 and the national base beneficiary premium will be $41.33, up from $38.99. The Part B deductible is projected to rise from $283 to $292. None of these increases is limited by the hold-harmless rule.

The $90 Rebate Detour

Adding to the confusion, President Trump announced on October 2, 2026, a one-time $90 rebate for about 20.8 million original Medicare beneficiaries, AARP reported. Medicare Advantage enrollees, IRMAA payers and people receiving Medicaid premium help are not eligible. KFF noted the payments, funded from the Medicare Improvement Fund, would nearly deplete that fund. The rebate is separate from the hold-harmless rule and does not change how your 2027 premium is calculated.

Longer Term, the Squeeze Continues

The Trustees project the Part B premium will reach $272.10 by 2031, an average increase of about 6% a year, while COLAs are projected to average 2.4% a year from 2027 to 2031, according to AARP. If those forecasts hold, more years like 2026 are likely, and the hold-harmless rule will matter again for retirees with small benefits.

Medicare Advantage Members Are in This Too

Joining a Medicare Advantage plan does not replace the Part B premium. Advantage enrollees still owe the standard Part B premium, and for most people it is still deducted from Social Security, so the hold-harmless rule can apply to that portion in the same way it does for people in original Medicare. Some Advantage plans offer a Part B “giveback” that reduces the amount withheld. Any separate premium your Advantage or Part D plan charges is outside the rule’s protection, even when it comes out of the same check.

Reading the Notice Line by Line

Your COLA notice shows three numbers that matter: your new gross monthly benefit, the Medicare premium deducted and the amount you will actually receive. To check whether hold-harmless applied, compare the net amount with what you received in December 2026. If the net is the same and your Part B deduction is below the standard premium, you were held harmless. If your net dropped and you think you met the conditions, call SSA at 1-800-772-1213 before assuming an error. Changes in tax withholding or a plan premium deduction can also move the net figure.

Your 2027 Calendar and Action Plan

1. Oct. 14, 2026SSA announces a 3.6% COLA for 2027.
2. Oct. 15 to Dec. 7Medicare open enrollment for 2027 plans.
3. Mid-Nov. 2026CMS expected to release official 2027 Part B premium and deductible.
4. Nov. 18, 2026Deadline to sign up for paperless notices to see your COLA notice online early.
5. Late Nov. 2026COLA notices, including 2027 Medicare premium, appear in my Social Security accounts.
6. December 2026Paper COLA notices mailed.
7. Dec. 31, 2026Increased SSI payments begin.
8. January 2027Higher Social Security benefits and new Part B premium take effect.

1. Open your COLA noticeCheck the gross benefit, the Part B deduction and your net payment for 2027.
2. Compare with your 2026 net paymentIf your net check fell and you meet the conditions, ask SSA why.
3. Check for IRMAAIf your income fell after a life-changing event such as retirement, you can ask SSA to reconsider with Form SSA-44.
4. Review Part D and Advantage costsUse open enrollment, which ends December 7, to compare plans.
5. See if you qualify for helpMedicare Savings Programs can pay Part B premiums for people with limited income.

• COLA notice onlineLate November via my Social Security
• Net check ruleCannot drop due to Part B
• Break-even benefitAbout $183 for 2027, indicative
• IRMAA uses 2025 incomeAbove $109,000 single in 2026
• Open enrollment endsDecember 7, 2026
• Part D cap$2,400 in 2027, reported