What a 3.9% Social Security COLA in 2027 Would Add to Your Monthly Check

Even though 2026 isn't even halfway done, many Social Security recipients are wondering what cost-of-living adjustment, or COLA, they might get in the new year. And while we won't have a solid handle on that number until October, since COLAs are calculated based on inflation changes in July, August, and September, economic data along the way can provide some clues.

In April, the Consumer Price Index for Urban Wage Earners and Clerical Workers (CPI-W) increased 3.9% on an annual basis. That's the specific index COLAs are based on. Following that report, the Senior Citizens League, an advocacy group, put out a 3.9% COLA estimate for Social Security benefits in 2027.

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You may be wondering how much of a raise that might amount to. The answer is, it depends on what your current monthly benefit looks like as well as another key factor.

The average Social Security benefit could get an $81 boost -- or much less

As of April, the average monthly retirement benefit paid by Social Security was $2,081. Based on that, if we apply a 3.9% COLA, it means the average senior on Social Security could see benefits rise by $81 in 2027.

However, there's more to the story.

Seniors who are enrolled in Social Security and Medicare at the same time pay their Part B premiums out of their monthly benefits automatically. When there's a big jump in the cost of Part B from one year to the next, it can eat into whatever COLA comes through.

This year, the cost of Medicare Part B increased from $185 to $202.90. If there's a similar increase in 2027, a 3.9% COLA could leave the average Social Security recipient with a much smaller net raise.

It's too soon to know how much Social Security benefits or Medicare will increase

If you're on Social Security and Medicare, you may be hoping to get answers soon on what to expect in the new year. But the Social Security Administration (SSA) cannot announce a COLA until September's CPI-W reading comes in.

As of now, that report is expected to come out on Oct. 14. So you can mark your calendar to stay tuned for a big Social Security announcement that day, assuming a government shutdown doesn't delay things as it did in 2025.

But even once the SSA announces an official COLA for 2027, you may not be able to calculate what it means for your monthly checks until an official Medicare announcement on Part B costs is made.

It's not unusual for the Centers for Medicare & Medicaid Services to announce its Part B figures in November. So, unfortunately, come mid-October, you may only have one piece of the overall puzzle.

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