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Enrollment

What the Annual Enrollment Period is for — and what it isn't

October 15 to December 7 is the window where most Medicare changes are allowed. It is also the window where the marketing gets loudest, so it helps to know what you can and cannot do.

5 min read

Every year between October 15 and December 7, Medicare opens its Annual Enrollment Period. Anything you change during that window takes effect January 1. It is the most flexible stretch of the Medicare year and, not coincidentally, the stretch where your mailbox fills up.

What you can change

  • Switch from Original Medicare to a Medicare Advantage plan, or back again.
  • Change from one Medicare Advantage plan to a different one.
  • Join, drop or switch a Part D prescription drug plan.

What the window does not cover

The Annual Enrollment Period does not give you a guaranteed right to buy a Medicare Supplement policy. That is the most widely misunderstood part of the calendar. You can apply for a supplement at any time of year, but outside your one-time six-month Medigap open enrollment window — and outside a few guaranteed-issue situations — the insurer can review your health history and turn you down.

It also is not the only window that exists. There is a Medicare Advantage Open Enrollment Period from January 1 to March 31 for people already in an Advantage plan, which allows one switch to another Advantage plan or back to Original Medicare. And Special Enrollment Periods open when your life changes: you move, you lose employer coverage, your plan leaves your county, or you qualify for Extra Help.

How to use the window well

Start with the Annual Notice of Change your plan mailed you in September. Read the sections on premium, out-of-pocket maximum, drug tiers and network changes. Then check three things: are your doctors still in network for next year, are your prescriptions still covered at the same tier, and did the out-of-pocket maximum move.

If all three answers are unchanged, doing nothing is a legitimate decision. Staying put is not laziness when the plan still fits.

On the marketing

Medicare marketing rules prohibit unsolicited door-to-door sales, require agents to get your permission before discussing plans, and require the multi-plan disclaimer you see at the bottom of this page. If someone pressures you to decide on the spot, refuses to put costs in writing, or claims to be calling from Medicare itself, end the call. Medicare does not cold-call beneficiaries to sell plans.

The right posture for the fall is unhurried. You have almost eight weeks. Nothing good comes from deciding in the first phone call you answer.


This article is general education and is not advice about your individual situation. Plan availability, costs and formularies change annually and vary by county. We do not offer every plan available in your area. Any information we provide is limited to those plans we do offer in your area. Please contact Medicare.gov, 1-800-MEDICARE, or your local State Health Insurance Assistance Program to get information on all of your options.

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