A 3.9% cost-of-living adjustment (COLA) would be a bigger Social Security raise than retirees have seen the past two years, and for people who’ve watched their checks barely keep pace with rising prices, that number sounds encouraging.
But a bigger COLA does not automatically mean more spending power. Between expected Medicare premium increases and the way the adjustment formula works, the gap between what the raise looks like on paper and what it does for your retirement plan could be wider than the headline suggests.
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Where the 3.9% estimate comes from
The Senior Citizens League, a nonprofit advocacy group, currently projects a 3.9% COLA for 2027, up from an earlier estimate of 2.8%.
The Committee for a Responsible Federal Budget (CRFB) puts it at around 3.8%, though they note the final number could fall anywhere between 3.0% and 4.5% depending on how inflation moves over the summer.
Both projections are based on recent readings of the CPI-W, the consumer price index that the government uses to calculate the annual adjustment. Energy costs, food prices, and housing have all been pushing that index higher in recent months.
The final COLA won’t be set until the Bureau of Labor Statistics releases CPI-W data for July, August, and September, with the official announcement expected in mid-October.
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How much of the COLA Medicare takes off the top
Medicare Part B premiums are projected to rise to about $218.60 a month in 2027, up from $202.90. For many retirees, the Part B premium is deducted from their Social Security payment, so a higher premium can reduce the net increase they actually see. On a 3.9% raise, Medicare alone could absorb $15 to $20 of the monthly gain, leaving around $60 in extra income after that deduction.
And that $60 then has to cover costs that have been rising faster than Social Security adjustments tend to keep up with. Housing, for instance, is a good example. Rent for a one-bedroom apartment now averages about $1,550 nationally, while the median Social Security check is under $2,000. When housing takes up that much of a monthly benefit, a modest raise typically doesn’t stretch very far.
The catch with how the COLA is calculated
By law, the COLA adjustment is based on inflation data from July through September of the prior year compared to the same three months a year earlier.
That means the 2027 adjustment will reflect price increases that already happened, not ones that are coming. If costs spike in October or November, retirees usually won’t see relief in their checks until the following January at the earliest.
Some senior advocates argue that Social Security has lost buying power over time because retiree costs, especially health care and housing, often rise faster than the COLA captures.
For instance, the 2025 and 2026 COLAs came in at 2.5% and 2.8%, adding up to about 5.4% over two years. For many retirees, that did not fully cover the price increases they faced during that same period.
A 3.9% bump in 2027 would help close the gap, but it is better understood as a partial recovery than as new spending power.
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How to plan before the number is final
The COLA won’t be official until October, and it won’t hit your check until January 2027. Between now and then, there are a few things worth doing.
For instance, you can take your current monthly benefit and apply a 3.9% increase to get a rough estimate of your new gross payment. Then subtract your projected Part B premium, which is expected to be around $218.60.
The difference between those two figures is a reasonable estimate of your actual net gain. For a lot of retirees, that number will be smaller than the percentage alone suggests.
If you’re finding that the gap between your COLA increase and your rising expenses is growing each year, this is a good time to review whether you qualify for any assistance programs. Medicare Savings Programs can cover Part B premiums for people under certain income thresholds. The Low Income Subsidy program, also called Extra Help, can help reduce Part D prescription costs.
You can also watch the BLS inflation reports in mid-August and mid-September. Those are the last two data points that will affect the final COLA.
If inflation picks up over the summer, the adjustment could fall near the high end of the 3.0% to 4.5% range. If it slows, the final number could come in lower. Budgeting around a conservative estimate gives you more room to adjust either way.
Bottom line
A 3.9% adjustment would be welcome, and for some retirees it will make a noticeable difference. For others, the gap between the gross increase and what’s left after Medicare premiums and higher living costs will be harder to feel.
Knowing exactly where you fall before January gives you time to adjust your retirement goals around what the raise will actually do for your budget.
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