Medicare Open Enrollment 2027: Key Dates and Your Countdown Checklist

Your Countdown to Medicare Open Enrollment Just Started

Mark your calendar: Medicare's Open Enrollment Period — officially called the Annual Election Period — runs from October 15 through December 7 every year, with any changes you make taking effect on January 1. That window is now just around the corner, which means it's the right moment to look at your coverage before the season gets busy and decision fatigue sets in.

Open Enrollment is the one guaranteed time each year you can make changes without a qualifying life event — so even if you're happy with your current plan, it's worth a quick check.

What You Can Actually Change During This Window

A lot of people assume Open Enrollment is only for switching Medicare Advantage plans, but the window covers more ground than that:

• Switch Medicare Advantage plans — join a new one, drop one, or move between plans with or without drug coverage.
• Change your standalone Part D drug plan if you have Original Medicare.
• Move between Original Medicare and Medicare Advantage in either direction.
• Add drug coverage or explore Medigap options if you're switching to Original Medicare.

Anything you submit needs to be received by the plan before December 7 in order to take effect January 1 — there's no grace period after that.

Why "It Worked Fine Last Year" Isn't Enough

Plans are allowed to change their premiums, deductibles, drug formularies, and provider networks every single year — even if you don't change a thing. A medication that was covered last year might move to a higher tier. A doctor's office that was in-network might not be next year. None of that shows up unless you actually compare your plan's new details against what you're using it for.

Your Open Enrollment Checklist

• Pull your "Annual Notice of Change" letter. Every Medicare Advantage and Part D plan is required to mail this each September, and it spells out exactly what's changing for next year.
• List your current medications and dosages. Then check next year's formulary and tier placement for each one — this is where the biggest cost surprises usually hide.
• Confirm your doctors and specialists are still in-network for the coming plan year, not just this one.
• Compare your total out-of-pocket picture — premium, deductible, copays, and the plan's out-of-pocket maximum — not just the monthly premium in isolation.
• Check whether your plan's service area changed if you split time between two locations or are planning to relocate.

A Word on Timing and Peace of Mind

You don't need to make a decision the first week of the window, but you also don't want to be comparing plans on December 6. Give yourself time to actually read the notice of change letter, make a couple of calls if something looks off, and sit with the decision for a day or two. Rushed Medicare decisions are how people end up locked into a plan that doesn't fit for a full year.

The Takeaway

Open Enrollment isn't about assuming something is wrong with your coverage — it's about confirming nothing quietly changed underneath you. A 20-minute review now can prevent a frustrating (and expensive) surprise in January. If you want a second set of eyes on your notice of change letter or just want to talk through whether your coverage still fits your situation, we're happy to help — no obligation.

Source: Medicare.gov, "Open Enrollment," accessed September 2026.