Will Your 2027 Social Security Raise Beat Medicare's Increase?

Two numbers will decide whether your January Social Security deposit feels like a raise. The first is the cost-of-living adjustment, which the Social Security Administration announces October 14. The second is the Medicare Part B premium, which comes out of your check before the money arrives and won't be official until CMS publishes it, typically in mid-November. Last year the premium won that contest by a wide margin. Early estimates for 2027 point the other way, but they are estimates, and one of them has a real chance of moving. Here is the math on both, what could knock it off course, and what to do before the numbers are final.

The two numbers, and when each one becomes real

The COLA is calculated from the average of the July, August, and September readings of the CPI-W, the consumer price index for urban wage earners and clerical workers. Two of the three are already in: 3.4% in July and 3.5% in August, both measured year over year. The September reading arrives October 14 at 8:30 a.m. Eastern, and the Social Security Administration announces the official adjustment right after it. The Senior Citizens League currently projects 3.5%, down a tenth from its August estimate. AARP is at 3.6%, and the low end of published estimates sits near 3.2%. For context, the 2026 adjustment was 2.8%.

The Part B side is less settled. The 2026 Medicare Trustees Report projects a standard 2027 premium of about $209.50, up $6.60 from this year's $202.90, an increase of roughly 3.25%. That is far smaller than the 9.7% jump in 2026. But it is a projection, and the Trustees have moved it before: the 2025 report had projected $218.60 for 2027, and we explained in our 2027 IRMAA projection why that older number is out of date. Some private forecasters still expect the final figure to land above the Trustees' baseline, around $216 or higher. The Part B deductible is projected to rise from $283 to about $292. For every 2027 figure in one place, see our 2027 Medicare hub.

Sources: The Senior Citizens League, Kiplinger, The Motley Fool, AMAC

What a $2,000 check actually looks like

Use a round number to see the pattern. On a $2,000 monthly benefit, last year's 2.8% COLA added $56. The Part B premium rose $17.90, from $185.00 to $202.90, which left a net gain of $38.10. About a third of the raise was gone before it arrived.

For 2027, a 3.5% COLA would add $70. If Part B lands at the Trustees' projected $209.50, it takes back $6.60, leaving a net gain of $63.40. Only about 9% of the raise is absorbed. The average retired worker's benefit was about $2,083 in July, so a 3.5% adjustment would add roughly $73 to that check and net out near $66 after the projected Part B increase.

Now stress the estimate the way a cautious planner would. If the COLA comes in at the low end, 3.2%, and Part B lands near $216 instead of $209.50, the raise is $64, the premium takes back $13.10, and the net is $50.90, with about a fifth of the raise absorbed. That is a worse year than the base case, and it is still better than 2026. The full scenario table is below. These figures cover the standard Part B premium only. They do not include IRMAA surcharges or any Part D premium withheld from your check.

Sources: The Senior Citizens League, TheStreet, our 2026 breakdown

What could throw the math off

Four things could change the picture before your January deposit. First, the September inflation reading. Two of the three months are already in, so a swing is unlikely, but the estimates have already moved a tenth of a point twice this summer, and the official number is only the average of all three.

Second, the Part B premium itself. The $209.50 projection is the Trustees' baseline, not CMS's final answer. Private forecasters have pointed out that the Trustees have missed in both directions before. If you want a margin of safety, plan around the higher figures in the scenario table rather than the lower ones.

Third, Part D. The federal program that held down standalone drug plan premiums in 2025 and 2026 ends after this year, and the national base beneficiary premium rises 6%, the maximum the law allows through 2029, to $41.33. CMS Administrator Dr. Mehmet Oz has said most people will see increases of less than $10 a month, and some will see decreases; outside analysts, including Avalere Health, are more cautious. If you have your Part D premium withheld from Social Security, any increase comes out of the same check. Our Part D changes page covers the deductible, the out-of-pocket cap, and the subsidy ending.

Sources: CMS fact sheet on 2027 Part D bid information, Managed Healthcare Executive, Medical Daily

What to do between now and mid-November

Start by finding your gross monthly benefit and what is currently withheld for Medicare, both of which are in your online Social Security account. You can't run the math without them. On October 14, write down the official COLA and calculate your raise in dollars. In mid-November, when CMS publishes the official Part B premium, subtract the increase and you have your real number.

In the meantime, open your Annual Notice of Change when it arrives. Our guide to why that September letter matters explains what to check. Then use the enrollment window, October 15 through December 7, to compare drug plans, because the end of the subsidy program makes premiums more plan-specific than they have been. KFF research has found that about seven in ten people with Medicare don't compare plans during open enrollment. Our guide on whether to switch plans before December 7 walks through the decision.

If your Medicare costs are a real strain, check whether you qualify for a Medicare Savings Program, which can pay your Part B premium entirely. Our guide to help with Medicare premiums covers the income limits. We will update this page with the official COLA on October 14 and the official Part B figures when CMS publishes them.

Table 1 — The 2027 numbers and where each stands

Table 2 — What a $2,000 monthly benefit nets (standard Part B premium only)

Illustration only. Excludes IRMAA surcharges and Part D premiums. The $216 stress-case premium is the low end of private forecasts, not a CMS figure. Sources: SSA; CMS; 2026 Medicare Trustees Report; The Senior Citizens League.