United States · SSA & BLS
Social Security COLA calculator.
Enter the CPI-W figures and your benefit to see the cost-of-living increase, with a Medicare Part B check. The September 2026 CPI-W decides the 2027 COLA and is out in mid-October.
The COLA is the percentage by which the July-September average CPI-W beats the July-September average of the last COLA year (317.265 for 2025), rounded to the nearest 0.1%. The 2026 COLA was 2.8%. The 2027 COLA is not announced yet; this page shows a projection until you enter the September figure.
Your inputs
Your COLA
How the COLA is set
By law (42 U.S.C. 415(i)), SSA averages the CPI-W for July, August and September of the current year and compares it with the same three-month average from the last year a COLA took effect. If the increase rounds to more than zero, that rounded percentage (nearest tenth of a percent) is the COLA, effective for December benefits and paid in January. If not, there is no COLA. SSA announces it right after BLS publishes the September CPI.
Worked example: the 2026 COLA
Q3 2024 averaged 308.729 (308.501, 308.640, 309.046) and Q3 2025 averaged 317.265 (316.349, 317.306, 318.139). (317.265 − 308.729) / 308.729 = 2.76%, which rounds to 2.8%. On a $2,000 benefit that is $56 a month. For 2027 the base is 317.265, because the 2025 COLA took effect.
Medicare Part B
Most people have the Part B premium deducted from their Social Security payment, so the check that lands is the COLA-raised benefit minus the new premium. The 2026 standard premium is $202.90, up from $185.00 in 2025 (CMS). The 2027 premium is not announced. A hold-harmless provision can limit the premium increase for some people whose premium is deducted, so use the Part B field as a what-if, not a guarantee.
Official sources: SSA COLA history table, SSA latest COLA and computation, BLS CPI-W series CWUR0000SA0 and CMS 2026 Part B premiums. Numbers verified October 1, 2026.
Every Social Security COLA since 1975
The first COLA was effective June 1975; the 1975-82 COLAs took effect in June, and every one since has been effective for December benefits. Years follow SSA's table: the year shown is the year the increase takes effect. The 1999 figure is the 2.5% set by Public Law 106-554 (originally 2.4%). Average over 2016-2025: see below.
| Year | COLA | Effective |
|---|
The ten COLAs from 2016 to 2025 average 3.11% and compound to 35.5% (calculated from the SSA table above).
Frequently asked questions
When is the 2027 Social Security COLA announced?
After BLS publishes the September 2026 CPI, which is scheduled for mid-October. SSA announces the COLA that same day. Until then any 2027 figure is an estimate.
How is the COLA calculated?
It is the percentage rise in the average CPI-W for July through September over the same average for the last year a COLA took effect, rounded to the nearest 0.1%. A zero or negative result means no COLA.
Is the COLA based on CPI-W or the regular CPI?
CPI-W, the index for urban wage earners and clerical workers, not CPI-U. The two often differ by a tenth of a point or more.
Will Medicare Part B take my whole raise?
Not necessarily. The 2026 standard premium is $202.90 and the 2027 amount is not announced. The page shows your net change once you enter a premium, and a hold-harmless rule can protect some people from a premium rise that exceeds their benefit increase.
Does SSI get the same COLA?
Generally yes, SSI payments rise by the same percentage, usually effective a month after the Social Security increase, according to SSA.
Has there ever been no COLA?
Yes. SSA's table shows 0.0% for 2009, 2010 and 2015.
Cite this page: TNAADO Tools, "Social Security COLA Calculator," tools.tnaado.ca/us/social-security-cola-calculator.html, data verified October 1, 2026 (SSA, BLS, CMS).
Estimate only
This is an educational estimate, not an SSA determination. Your actual benefit depends on your own record, withholding and Medicare deductions. The official COLA is whatever SSA announces.