The Bureau of Labor Statistics will publish the September 2026 Consumer Price Index on October 14 at 8:30 a.m. Eastern, the last data point the Social Security Administration needs to calculate the raise that takes effect for 2027. SSA’s formula compares the average Consumer Price Index for Urban Wage Earners and Clerical Workers across July, August and September against the same three-month average from the last year a cost-of-living adjustment took effect. No 2027 percentage has been calculated or announced.
Inside the kit: The 2026 payment calendar in The Social Security Check Protection Kit maps the day-of-month schedule, and a first-24-hours plan covers a deposit that’s late or doesn’t match. See the payment-day schedule the raise will follow →
The Third-Quarter Comparison Behind Every COLA
Social Security’s cost-of-living adjustment is not an estimate or a political decision each fall; it is the output of a fixed formula published by the agency’s own Office of the Chief Actuary. “A COLA effective for December of the current year is equal to the percentage increase (if any) in the CPI-W from the average for the third quarter of the current year to the average for the third quarter of the last year in which a COLA became effective,” according to the Social Security Administration’s official COLA-calculation page. The result is rounded to the nearest tenth of a percentage point, and if that rounded figure is zero or negative, no COLA is granted at all that year. SSA’s general COLA information page states the underlying principle plainly: “Social Security’s general benefit increases have been based on increases in the cost of living, as measured by the Consumer Price Index,” according to the Social Security Administration’s Cost-Of-Living Adjustment information page, rather than a legislated raise Congress votes on each year.
Why This Specific Inflation Index, Not The Headline Number
The figure that sets Social Security’s raise is not the broader inflation rate most news coverage quotes each month. The Bureau of Labor Statistics publishes several versions of the Consumer Price Index in the same monthly report, and the one SSA’s formula uses is the CPI-W, tracking the spending patterns of urban wage earners and clerical workers specifically, rather than the CPI-U index used for other purposes. The two indexes tend to move together but are not identical, since they weight household spending categories differently, which is part of why an outside estimate of the COLA can differ from the number SSA eventually publishes even when both sides are reading the same set of Bureau of Labor Statistics reports.
Why October 14 Is The Date That Completes It
The third quarter runs July through September, and the Bureau of Labor Statistics releases each month’s CPI-W figure on its own fixed date roughly six weeks after the month ends. The Bureau of Labor Statistics’ published release schedule lists the September 2026 report for October 14, 2026 at 8:30 a.m. Eastern, following the August figure that BLS had already released on September 11. Once the September number is public, the three-month average behind the 2027 COLA is fixed, and the Social Security Administration can finish the calculation rather than wait on any further data.
What The Formula Will Compare The September Figure Against
The other half of the equation is not this year’s inflation alone but a year-over-year comparison. SSA’s formula measures the percentage change between the current year’s third-quarter CPI-W average and the third-quarter average from the last year a COLA actually took effect, which was 2025 for the adjustment that began in January 2026. That means the October 14 release does not, by itself, reveal the 2027 COLA; SSA still has to complete the comparison against that 2025 baseline, and until it does, any specific percentage circulating publicly is an outside estimate rather than an official figure. The most recent completed adjustment, effective for December 2025 and reflected in the payments that began arriving in January 2026, was 2.8 percent, according to the Social Security Administration’s own October 24, 2025 announcement, compared with 2.5 percent for the adjustment the year before. That prior figure is not itself part of the 2027 math; it only marks which third-quarter CPI-W average the new September data will be measured against, per the same SSA COLA-calculation page.
No Percentage Yet — And No Official Announcement Date Confirmed
Neither the Bureau of Labor Statistics nor the Social Security Administration has published a 2027 COLA percentage as of this article, and SSA’s own COLA page does not commit to a specific calendar date for the announcement. The precedent from last year offers a rough guide: SSA announced the 2026 COLA on October 24, 2025, later the same month as that year’s final third-quarter CPI-W release, according to the agency’s own press release. Retirees should look to SSA’s own announcement, not an earlier outside estimate, for the confirmed 2027 number.
What A Retiree Can Actually Do Before The Number Is Known
Nothing about the October 14 release changes a benefit amount by itself, since the COLA formula, not any single monthly reading, determines the 2027 figure. What the October 14 date does mark is the point after which SSA has every input it needs, so the finalized percentage becomes a matter of the agency completing its own calculation and publishing it rather than waiting on additional inflation data. A retiree drawing Social Security can expect the resulting adjustment to first show up in the January 2027 payment, while SSI recipients typically see a COLA reflected the month it takes effect, following the same pattern SSA used for the 2026 COLA, when Social Security payments rose starting in January and SSI payments rose starting Dec. 31, 2025. SSA’s own notice for each beneficiary remains the authoritative confirmation of the exact new amount, not a news report or an outside estimate published before that notice arrives.
What A Percentage Doesn’t Tell A Retiree About Their Own Check
Once SSA finishes comparing the September CPI-W figure against its formula, the resulting percentage still has to be applied to each individual’s own benefit amount and land correctly on the right payment date. A raise that doesn’t show up on schedule, or shows up smaller than expected, raises the same practical questions as any other payment problem.
The Social Security Check Protection Kit includes the 2026 payment calendar, the three SSA forms that stop or pause collection if a notice about the new amount raises a dispute, and a first-24-hours plan for a payment that arrives late or doesn’t match what was expected.
Check the payment calendar and the first-24-hours steps in The Social Security Check Protection Kit.
This article was produced with AI assistance and checked against the primary sources linked above.
David M. Keller is a finance writer based in Columbus, Ohio, covering personal finance and consumer-focused economic topics. He earned his degree in journalism from Ohio University and began his career reporting on local business and economic trends for a regional media outlet. Since then, he has contributed to a variety of online publications, focusing on clear, practical coverage of topics such as cost of living, debt, and everyday financial decision-making.
