Two things are true at once this month, and most coverage manages to state only one of them. First: Medicare Open Enrollment ends on December 7, 2026, and for millions of people that deadline is the last chance to change their coverage for 2027. Second: the Part B premium figure repeated across the internet — $209.50 a month — is not an official number. It is a projection. As of November 6, the Centers for Medicare & Medicaid Services (CMS) had not announced the actual 2027 premium at all. Both facts matter, and confusing the second one is how readers end up planning around a number that may never exist.
The December 7 Deadline: What It Covers
Open Enrollment — the annual window that opened in mid-October — is when current Medicare beneficiaries can switch between Original Medicare and Medicare Advantage, change Advantage plans, or join, switch or drop a Part D prescription drug plan, with the new coverage starting January 1, 2027. December 7 is the final day for those changes. Miss it, and in most cases your current coverage simply rolls into 2027 as it is; the next broad chance to change is a year away, outside of the narrower Medicare Advantage Open Enrollment Period (January 1 to March 31, for Advantage members only) and special enrollment periods triggered by life events like a move. If you are content with your plan and it is renewing on acceptable terms, doing nothing is a legitimate choice — the deadline only bites if you wanted a change.
$209.50 — Projection, Not Announcement
Now the number. The standard Part B premium in 2026 is $202.90 a month. The figure of $209.50 for 2027 comes from the Medicare Trustees' annual report — the official actuaries' best estimate, published months before CMS finalizes the real premium. A projection is not a rumor; it is serious work by the program's own trustees, and the final number often lands near it. But it is not an announcement, and the gap between the two matters: CMS computes the premium from updated spending data late in the year and was expected to publish the official figure around mid-November. Until that release exists, any headline stating $209.50 as the 2027 premium is stating something that has not happened. Our rule on this page is simple, and we apply it to ourselves: projections are labeled projections, every time.
$209.50 is the Trustees' projection. The official premium does not exist yet — and the difference decides real budgets.
What The Trustees' Report Actually Says
Beyond the headline premium, the same Trustees' projection puts the 2027 Part B deductible at $283 — again, projected, not official. The report is the trustees' modeling of where program costs are heading: physician services, outpatient care and the rest of what Part B pays for. Premiums are set to cover roughly a quarter of Part B's expected costs for beneficiaries aged 65 and over, which is why the number tends to climb as medical spending climbs. Understanding that machinery helps cut through two opposite exaggerations. The premium is not arbitrary, and it is not yet fixed either — it is a formula applied to forecasts, and the last step of that process, CMS's official release, is the one still pending.
How Part B Eats Your COLA
The reason the projection matters so much is its collision with the other big number of the season: the 3.6% Social Security COLA for 2027, which adds about $75 a month to the average retired worker's check. For most beneficiaries, the Part B premium is deducted straight from that check. If the premium rises by the projected amount — $209.50 against 2026's $202.90 is a $6.60 increase — the raise still wins comfortably for an average check. But the arithmetic tightens for smaller benefits, and a 'hold harmless' provision protects many long-term beneficiaries from having their net check reduced by a premium increase — though it does not cover everyone, including newer beneficiaries and those who pay income-related premium surcharges. The honest summary: the official premium, when it lands, will decide how much of the COLA you actually see — which is precisely why it should not be reported as settled before it is.
What To Check Before You Switch (Or Stay)
You do not need the final premium to make good use of the weeks before December 7. Start with what you can verify now: whether your doctors and hospitals remain in your plan's 2027 network, whether your prescriptions are still covered and at what tier, and what your plan's annual notice of change — the document your insurer sent this fall — says is different next year. Compare total likely costs, not just premiums: a cheaper plan with your medications re-tiered can lose money by March. Use the official comparison tools at Medicare.gov, and if the premium announcement lands while you are deciding, fold the official figure — not the projection — into your math. We will update this article the day CMS publishes the real 2027 premium, clearly marked as the official number. Until then: December 7 is real, $209.50 is a forecast, and your decision deserves both facts at once.
