Medicare Open Enrollment in California: What to Review Before You Change Coverage

Know which enrollment period you are using

Medicare Open Enrollment runs October 15 through December 7 each year. During this window you can join, drop, or switch a Medicare Advantage plan, or add, drop, or switch a Medicare drug plan. You can also switch between Original Medicare and a Medicare Advantage plan in either direction. A change made during this window generally starts January 1, as long as the plan receives the request by December 7.

This is not the only time some people can make a change. If you are already enrolled in a Medicare Advantage plan, a separate Medicare Advantage Open Enrollment Period runs January 1 through March 31 each year; if instead you are new to Medicare and are joining a Medicare Advantage plan for the first time, that same kind of window runs from the first month you have both Part A and Part B through the last day of your third month of having both. During that window you can switch to a different Medicare Advantage plan, or drop Medicare Advantage and return to Original Medicare and join a separate Medicare drug plan, but Medicare limits you to one change during that period each year. Most people enrolling in Medicare for the first time instead use their own Initial Enrollment Period, based on when they first become eligible for Medicare, such as turning 65, not the fall dates above. Confirm which window applies to you before assuming you are out of time, or that you still have time.

Medicare Supplement Insurance, also called Medigap, is generally not part of this Open Enrollment window. If you are considering dropping a Medicare Advantage plan and returning to Original Medicare, do not assume you can add a Medigap policy without health questions. Outside specific situations that give you a guaranteed-issue right, an insurer can generally ask health questions and may deny an application or charge more. Confirm your own guaranteed-issue rights with Medicare, HICAP, or the California Department of Insurance before dropping a Medicare Advantage plan, rather than relying on this page.

Review what is changing before you decide

Medicare health and drug plans can change their costs, coverage, and provider or pharmacy networks every year. Your plan sends an Annual Notice of Change that describes what is changing for the coming year, and an Evidence of Coverage that describes the plan's full benefits and rules (sometimes the plan sends a notice telling you where to find the current Evidence of Coverage online rather than mailing the whole document). Read what you receive before deciding anything, even if you were satisfied with your coverage last year.

Make a private list of what actually matters to your care: the monthly premium, deductible, and copay or coinsurance amounts; whether your doctors and hospitals are still in the plan's network; whether your prescriptions are still covered and at what tier; whether your pharmacy is still in-network; and whether any extra benefits you rely on are changing. Plan networks, drug lists, pharmacies, and costs can change from one year to the next, and the details vary by county, so check current information rather than assuming last year's answer still holds. A general guide like this one cannot tell you whether to keep or change your own coverage; check current information with Medicare Plan Compare, the plan, and your providers, and do not change coverage based only on a brochure, advertisement, or this page.

If, after reading what you received, you are satisfied that your current plan will meet your needs next year and it is still being offered, you generally do not have to do anything. If your current plan is not being offered again, you will get a separate nonrenewal notice explaining your options and deadlines, and it works differently from a routine Annual Notice of Change, so read it closely.

Common reasons people take a second look

You do not need a special reason to review your coverage, but certain changes are common triggers: you moved within California and want to confirm your plan's service area and network still fit; a doctor, specialist, or hospital you use left the plan's network; a prescription's tier, cost, or pharmacy coverage changed; your health needs changed enough that different benefits matter more now; or you were simply dissatisfied with the plan's service this year. Any of these is a reasonable prompt to reread your notices and confirm current details. A move can also open its own separate Special Enrollment Period outside this fall window, so check the timing that applies to your own situation rather than assuming December 7 is always the relevant date.

None of these situations changes the review process. Confirm the facts for your own plan and providers before deciding, rather than relying on a general description of what usually happens.

Bring your questions to the right person

A licensed insurance agent can discuss the products the agency represents and the questions to verify for your situation. California HICAP offers free, confidential Medicare counseling. Medicare.gov and 1-800-MEDICARE provide official plan information.

Before a conversation, write down what changed in your plan notice and which doctors, prescriptions, or pharmacies matter most. If your current plan continues and you do not make a change, your enrollment generally continues. Still, read the Annual Notice of Change and any nonrenewal notice closely, and keep a copy of whatever you decide for your own records.