The 2027 Social Security Raise Is About 3.5%. Here Is What Your January Check Will Actually Be.

Written October 11, 2026, three days before the announcement. The Social Security Administration publishes the 2027 cost-of-living adjustment on the morning of October 14, when the Bureau of Labor Statistics releases the September inflation report. Every figure below uses the 3.5% estimate the Senior Citizens League published in September (AARP says 3.6%), and the Medicare Part B premium the 2026 Trustees Report projects. The January-check engine carries both as editable figures, marked estimate and projected until the official numbers land, and this post will be updated the day they do.

How the number is built

The adjustment is not a decision anyone makes. It is the change in one price index, the CPI-W, averaged over July, August and September, against the same three months a year earlier. Two of the three months are already in.

For the final figure to land at exactly 3.5%, September's CPI-W needs to come in at about 329.5 — a 0.3% rise on the month, which is roughly what gasoline at a record $4.33 a gallon for September implies. A reading of 330 would round to 3.6%; one of 329 would round to 3.4%. The estimate has a narrow range because two-thirds of the arithmetic is already done.

For comparison, the 2026 adjustment was 2.8%, 2025 was 2.5%, and 2023 — the year the 2022 inflation spike fed through — was 8.7%. The Senior Citizens League's own buying-power study puts the loss since 2010, after every adjustment, at about 13.7%, because the CPI-W tracks the spending of working households rather than retired ones, and health care weighs heavier in the second.

What the raise does to an actual check

Here is where every "3.5% × your benefit" calculator on the internet goes wrong, three times over. Take the average 2026 retired-worker benefit of $2,071.00 a month, with Part B deducted.

SSA rounds down, twice. $2,071 × 1.035 is $2,143.485. SSA rounds the raised benefit down to the next lower dime: $2,143.40. The raise is $72.40, not $72.49. Then the premium comes out and the payment is rounded down again, to the next lower dollar.

Part B goes up in the same month. The 2026 standard premium is $202.90. The 2026 Medicare Trustees Report projects $209.50 for 2027, a $6.60 increase; Medicare publishes the final figure in November, and the last two years it has come in both above and below the projection. If the premium is deducted from the check — it is for most people on Medicare — the increase comes out of the raise.

The deposit moves less than the headline. December's payment is $2,071.00 − $202.90 = $1,868.10, rounded down to $1,868. January's is $2,143.40 − $209.50 = $1,933.90, rounded down to $1,933.

So about $65 of the $72.40 raise — 90% — reaches the average retiree. The January-check engine runs this arithmetic on your own benefit, with the rounding and the premium, and tells you which of the three things below applies to you.

The hold-harmless rule, and why it barely matters this year

Federal law stops a Part B increase from taking your January payment below your December payment, as long as the premium is deducted from your check in both months and you do not pay the income-related surcharge. It exists for years like 2016 and 2017, when the adjustment was 0% and 0.3% and the premium still rose.

With a 3.5% raise and a $6.60 premium increase, the rule only bites for benefits under about $190 a month — a small spousal or survivor benefit, mostly. It would matter far more if the final premium came in high. Run the engine with a different Part B figure under "fine-tune" to see where your own payment would be held. The rule does not protect the roughly 8% of enrollees who pay the surcharge, people who are billed for Part B directly, or people joining Medicare in 2027.

If you do pay the surcharge, note that your 2027 premium is set from your 2025 tax return. A one-time event that year — a Roth conversion, a house sale, a final year of full-time work — can be appealed with Form SSA-44, and the Medicare surcharge engine shows what each bracket costs.

The part no calculator shows: more of your benefit becomes taxable

Up to 85% of a Social Security benefit is taxable once your other income plus half your benefit — "combined income" — passes $25,000 for a single filer or $32,000 on a joint return, with a second line at $34,000 and $44,000. Those lines were written into law in 1984 and 1993. They have never been adjusted for inflation, and no bill to index them has passed. So every cost-of-living raise, by design, moves a little more of every benefit across them.

Take the same $2,071 benefit, a single filer, and $30,000 of other income from a pension and an IRA.

That is after the standard deduction, the extra deduction for age 65 and the $6,000 senior deduction that runs through 2028. The person's net raise is $780 for the year; $44 of it goes back in tax, on top of what they already paid on the benefit. It is a small number. The point is the direction: the lines do not move, the benefit does, and the share taxed can only rise.

The one input in that table a person controls is other income — which account a withdrawal comes from. The engine's Lever Board moves it $5,000 each way and shows what crosses the line. It does not say which way to move it; that depends on things it cannot see.

What this changes for you

If you are already collecting. Nothing to file. SSA mails your new amount in December and posts it in your my Social Security account at the start of the month. Budget on the deposited figure, not the gross one. If you want tax taken out, Form W-4V lets you have 7%, 10%, 12% or 22% withheld.

If you have not claimed yet. You do not lose the raise by waiting. It is applied to your record from age 62 whether or not you have started, and the figure on your statement already includes every past one. Waiting changes your check through the early-claiming reduction and delayed credits — the claiming-age engine works in today's dollars for exactly that reason.

If you are planning retirement. The raise is an inflation adjustment, not growth. A retirement projection that assumes 2.5% inflation and a benefit that keeps pace is already counting it; what it may not be counting is the Part B premium rising faster than the benefit, as it has in most years since 2000. The retirement calculator takes a separate inflation figure for that reason.

Frequently asked questions

When exactly is the 2027 COLA announced, and when does it show up? October 14, 2026, at about 8:30 a.m. Eastern, when the September CPI report is released. It applies to benefits paid in January 2027. Supplemental Security Income gets it on December 31, 2026, because the January 1 payment date falls on a holiday weekend. SSA letters go out in December.

Why do estimates say 3.5% and 3.6%? Because the third month is not in. The July–August average is 3.3% above last year's third quarter; the estimate depends on what September gasoline and shelter did. A September CPI-W of about 329.5 gives 3.5%; about 330 gives 3.6%. Both are within the normal error of a one-month forecast.

Does the Part B premium really go up every year? Nearly. It was $185.00 in 2025 and $202.90 in 2026 — a 9.7% rise, far more than that year's 2.8% adjustment. The $209.50 projection for 2027 is a 3.3% rise. The final figure is set by Medicare in November based on actual program costs, not by the Trustees' projection.

I get a FERS or CSRS pension. Is it the same raise? CSRS pensions use the same CPI-W figure, so about 3.5%. FERS pensions get one point less when the CPI-W rises more than 3%, so about 2.5% — and most FERS retirees under 62 do not receive it at all.

Will the raise push me into the Medicare surcharge? No. The surcharge is based on your tax return from two years earlier (2025 for 2027 premiums), and the first bracket starts above $109,000 of income for a single filer in 2026. A $65-a-month raise does not get anyone there.

Can the raise ever be zero? Yes — 2010, 2011 and 2016 were 0%, and 2017 was 0.3%. The law does not allow a negative adjustment, so in a year of falling prices benefits simply stay flat, which is when the hold-harmless rule does most of its work.

Sources and as-of dates. CPI-W for July and August 2026 and the 2025 third-quarter average: U.S. Bureau of Labor Statistics, via the Senior Citizens League and FedSmith (September 17, 2026). COLA estimates: Senior Citizens League, 3.5% (September 2026); AARP, 3.6% (September 11, 2026). Average retired-worker benefit, $2,071: Social Security Administration, January 2026. 2026 Part B premium, $202.90: Centers for Medicare & Medicaid Services, November 2025. 2027 Part B projection, $209.50: 2026 Medicare Trustees Report. Taxation of benefits: IRS Publication 915; thresholds under 26 U.S.C. §86. Hold-harmless: 42 U.S.C. §1395r(f). Rounding rules: SSA Program Operations Manual. 2026 brackets and deductions: Rev. Proc. 2025-32 and P.L. 119-21. Buying-power loss since 2010: Senior Citizens League, 2026 Loss of Buying Power report.

This article explains how the adjustment is computed and what it does to a payment. It is educational, not financial or tax advice. The 3.5% figure is an estimate until SSA publishes the adjustment on October 14, 2026, and the $209.50 premium is a projection until Medicare publishes the 2027 figure in November; both will be updated here when they are final.