Social Security COLA Calculator
Updated November 2026 · Free · No sign-up
Calculate what the Social Security COLA does to YOUR benefit — apply the announced (or projected) percentage to your monthly check, see the annual gain, and understand the Medicare premium offset that eats part of it.
Quick answer: New benefit = current benefit × (1 + COLA%). The COLA is announced every October (from Q3 CPI-W data) and hits January checks. A 2.8% COLA on a $1,900 benefit = +$53/month, $2,536/year total — before any Medicare Part B premium increase nets against it.
How the COLA Is Set
Every October, SSA compares the third-quarter (Jul-Aug-Sep) average CPI-W against the same quarter of the last year a COLA was applied. The percentage increase — rounded to the nearest 0.1% — becomes January's COLA. No increase if CPI-W falls (benefits never decrease). The same figure flows to SSI (December 31 payment), Social Security Disability, and survivor benefits; federal pensions use related but capped formulas.
Worked Examples
Example 1 — average retiree. $1,900/month at 2.8%: +$53.20/month → $1,953 — about $638 more across the year.
Example 2 — the Medicare offset. Same COLA, Part B premium rises $10: net gain $43.20/month. In low-COLA years the hold-harmless rule prevents Part B increases from cutting your check below last year's — small comfort, real protection.
Example 3 — compounding. COLAs compound: $1,900 through 3%, 2.5%, 2.8% consecutive years = $2,062 — the reason delayed claiming (bigger base) also means bigger dollar COLAs forever.
COLA Facts
| Item | Detail |
|---|---|
| Announcement | Mid-October (with September CPI release) |
| Effective | January benefits (December for SSI) |
| Index | CPI-W — not the senior-specific CPI-E, a perennial reform debate |
| Applies to | Retirement, disability, survivor benefits, SSI — automatically, no action needed |
| Also moves | The wage base ($184,500 in 2026 — see SS tax calculator), earnings limits, and max benefits move with wage/price indexes in parallel |
Reading October's Announcement Like a Planner
- Your exact increase: benefit × COLA, rounded down to the dime at each step of SSA's math — this calculator mirrors the headline math; your award letter settles cents.
- The net check: January's deposit = new benefit − Medicare premium − any withholding. Part B premiums announce in November — the COLA headline without the premium line is half the story.
- Taxes: a bigger benefit can pull more of it into taxability (the combined-income thresholds are famously unindexed) — the quiet COLA clawback for middle-income retirees.
- Still working? The earnings-limit thresholds also rise with the announcement — relevant to early claimers weighing the claiming-age decision.
Projection Season
Between July and October, analysts project the COLA from incoming CPI-W prints — projections narrow monthly and the October number rarely surprises by more than 0.1-0.2 points. Enter any projection above to preview your check; swap in the official figure when announced.
Frequently Asked Questions
How is the Social Security COLA calculated?
Q3 average CPI-W vs the prior COLA year's Q3, rounded to 0.1% — announced each October, applied to January benefits automatically.
How much will my check increase?
Current benefit × COLA%. A 2.8% COLA on $1,900 adds about $53/month — enter your own figures above for the exact math.
Does Medicare eat the COLA?
Part B premium increases deduct from the gross gain; the hold-harmless rule stops premiums from reducing your net check below the prior year's in low-COLA years.
When does the COLA take effect?
January payments (the December 31 payment for SSI). No action required — it applies automatically.
Can the COLA be zero?
Yes — if Q3 CPI-W doesn't rise (2010, 2011, 2016 were 0%). Benefits never decrease.
Does the COLA apply if I haven't claimed yet?
Your future benefit is wage-indexed until 62, then COLA-adjusted — delaying claims doesn't miss COLAs; they build into the eventual benefit.
✓ Formula verified • Last updated: November 3, 2026