Social Security COLA and Medicare: How much could your Medicare cost increase for next year?

For millions of Americans receiving Social Security, the size of next year's cost-of-living adjustment is only one part of the financial equation.

The amount beneficiaries actually keep from a higher monthly check will also depend on Medicare costs, particularly the premium for Part B.

The 2027 Social Security COLA has not yet been finalized. Current estimates are clustering around 3.5% to 3.6%, with the Senior Citizens League currently projecting 3.5% and other estimates putting the figure slightly higher.

The official adjustment will be calculated after September inflation data are released, with the announcement expected in October.

That means retirees should be cautious about treating any current percentage as guaranteed. The final COLA is based on the Consumer Price Index for Urban Wage Earners and Clerical Workers, or CPI-W, using inflation data from July, August and September.

The difference could nevertheless be meaningful for household budgets. Based on the latest 3.5% projection, an average Social Security benefit of around $2,086 per month would increase by roughly $73.

The precise dollar increase will vary considerably because Social Security payments differ from person to person.

But the gross increase is not necessarily what beneficiaries will see in their bank accounts.

Medicare Part B premiums are generally deducted directly from Social Security payments, making the annual Medicare announcement particularly important for retirees who rely heavily on Social Security.

Medicare Part B could take a portion of the 2027 Social Security increase

The latest official Medicare Trustees projections estimate that the standard monthly Part B premium could rise from $202.90 in 2026 to $209.50 in 2027. That would represent an increase of $6.60 per month, or $79.20 over a full year for someone paying the standard premium.

It is important to stress that $209.50 is a projection, not the final 2027 premium. CMS normally announces the official Medicare premiums later in the year.

The relationship between Social Security and Medicare is significant because the two increases do not operate independently from a retiree's perspective.

Ritter Insurance Marketing previously explained that Medicare Part B premiums are deducted from Social Security checks and that the federal "hold harmless" provision protects most Social Security beneficiaries from having their monthly Social Security payment fall below the previous year's level solely because of a Part B premium increase.

For example, if the eventual COLA were 3.5%, the average beneficiary could see a substantial increase in their gross Social Security benefit.

A $6.60 increase in the standard Part B premium would then consume part of that additional amount, although it would not erase the entire COLA .

Higher-income Medicare beneficiaries also need to consider Income-Related Monthly Adjustment Amounts, commonly known as IRMAA. These surcharges can substantially increase what some people pay for Medicare Part B and Part D.

The income used to determine 2027 IRMAA generally comes from a tax return filed two years earlier, meaning 2025 income is relevant for 2027 calculations.

That can make the headline Part B premium misleading for some households. Someone paying the standard premium could see a relatively modest increase, while a beneficiary subject to IRMAA could face a significantly larger monthly Medicare deduction.

There are also other Medicare expenses to watch. Projections for 2027 indicate that the Part B deductible could increase to $292, while changes to Part D premiums and the prescription-drug out-of-pocket structure could also affect household spending.

The timing is particularly important because Medicare's annual enrollment period begins October 15 and runs through December 7. Beneficiaries can use that period to review Medicare Advantage and Part D coverage for the following year.

For Social Security recipients, therefore, the 2027 COLA should not be viewed in isolation. A projected 3.5% or 3.6% increase could provide a larger monthly benefit, but Medicare premiums, income-related surcharges, prescription costs and other healthcare expenses will determine how much of that increase ultimately remains available for everyday spending.

Until the Social Security Administration and CMS publish their final figures, the safest approach is to treat the current numbers as estimates.

The important calculation for beneficiaries will not simply be how much their Social Security check rises, but how much remains after Medicare and other deductions are taken out.