If you're one of the more than 70 million people who receive Social Security, you already know the January check usually looks a little different from December's. That change is the COLA — the Cost-of-Living Adjustment — and for 2027, current estimates put it at the highest level since 2023. Here's exactly how it's calculated, when you'll know the real number, and what it means for your check.
The Rule in One Sentence
The COLA is the percentage change in the CPI-W (Consumer Price Index for Urban Wage Earners and Clerical Workers) between the third quarter of the current year and the third quarter of the last year a COLA was applied. Whatever that percentage is becomes next January's raise.
Why the 2027 Estimate Is Higher
The 2026 COLA came in at 2.8%, itself a modest bump from 2.5% in 2025. If the 2027 estimate holds at 3.5%–3.6%, it would be the largest annual increase since the 8.7% jump in 2023 — a sign that inflation, particularly around groceries and energy, picked back up over the summer of 2026 after a few calmer years.
For context: the COLA formula doesn't care why prices rose, only that they did. Whether it's fuel costs, food prices, or housing, the CPI-W simply captures the net change across a fixed basket of goods and services that working-age earners typically buy.
What This Means for Your Check
A 3.6% COLA on the average $2,071 monthly retirement benefit works out to roughly a $75 increase, bringing the average check to about $2,146. Your own number scales the same way — multiply your current monthly benefit by the COLA percentage to estimate your raise.
One thing that trips people up: the COLA increase and your take-home increase aren't always the same number. If you're enrolled in Medicare Part B, the premium is deducted directly from your Social Security check — and if that premium rises alongside the COLA, part of your raise effectively goes toward covering it before you ever see it.
Frequently Asked Questions
When is the 2027 Social Security COLA announced?
The Social Security Administration announces the official COLA on October 14, 2026, alongside the September CPI-W inflation report. The new amount takes effect with January 2027 benefit payments.
How is the Social Security COLA calculated?
COLA is based on the percentage change in the CPI-W between the third quarter (July, August, September) of the current year and the third quarter of the last year a COLA was applied.
Does the COLA increase get reduced by Medicare premiums?
For most beneficiaries enrolled in Medicare Part B, the standard premium is deducted directly from the Social Security check. If the Part B premium rises, it can offset part of the COLA increase, so the net increase in your deposited check may be smaller than the COLA percentage alone suggests.
What is the estimated 2027 COLA?
As of September 2026, independent estimates range from 3.5% (The Senior Citizens League) to 3.6% (AARP), based on CPI-W data through August 2026. The final figure depends on September's inflation report and won't be official until October 14, 2026.