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Medicare Advantage Enrollment in California

You can apply for a Medicare Advantage plan (also known as Medicare Part C) when you first become eligible for Medicare. There are also other times during the year when you can change your Medicare Advantage plan. For the most part, unless you are signing up for Medicare for the first time, Medicare Advantage enrollment periods occur at specific times throughout the year.

Medicare Advantage Enrollment Period

Whether you’re enrolling in Medicare Part C for the first time or want to make changes to an existing Medicare Advantage plan, there are many things to keep in mind. You’ll need to know if you qualify for an enrollment period, when your benefits will start, and what happens if you don’t meet the deadlines.

Can I enroll in a Medicare Advantage Plan anytime?

You can only enroll in a Medicare Advantage Plan during specific enrollment periods. If you are new to Medicare, we also have information about how to enroll in your Medicare Part A and B benefits and offer a comparison of Medicare Advantage vs. Original Medicare.

Enrollment Period What are the enrollment dates? Who can enroll during this time? What changes can I make? When will my benefits start if I sign up during this enrollment period? What if I miss this enrollment period?

Initial Enrollment Period

  • Begins three months before your 65th birthday.
  • Ends three months after your 65th birthday.
  • You can also sign up the month of your birthday.
  • Those who are turning 65, and “aging in” to Medicare, and who are not already receiving Social Security benefits.
  • You can enroll in Part A and/or Part B.
  • You can also enroll in Medicare Advantage (Part C) during your initial enrollment period, after enrolling in Part A and Part B.
  • Your benefits start on the first day of the month you turn 65 if you sign up during the 3 months before your birthday.
  • If your birthday is on the first of the month, benefits start the first day of the month before your birthday.
  • If you sign up during one of the 3 months after your birthday, your enrollment begins the first day of the following month. 
  • If you do not sign up for Medicare Advantage during your initial enrollment into Medicare, you will need to sign up during one of the other enrollment periods.

Annual Election Period

  • Each year, from October 15 to December 7.
For those who want to make a change in their plan, here are the types of changes you can make to Medicare Advantage plans:
  • Add a Medicare Advantage plan if you currently only have Original Medicare.
  • Switch from one Medicare Advantage plan to another type of Medicare Advantage plan.
  • Change from a Medicare Advantage plan that doesn’t have Prescription Drug coverage, to one that does.
  • Or switch from a Medicare Advantage (Part C) plan that has Prescription Drug coverage to one that doesn’t.
  • Enrollment in your new plan begins on January 1 of the following year.
  • If you miss open enrollment you will need to wait until the next year to change your Medicare Advantage plan, unless you meet the conditions of another enrollment period.

Special Enrollment Periods

  • Special time period based on your life experiences.
  • Those who have had a life change that qualifies them to switch or join a Medicare Advantage plan.
  • These may be related to many different things such as moving out of your plan’s service area, losing employee or other coverage, moving in or out of a nursing home, becoming eligible for Medicaid, or a plan with a 5-star rating becomes available.
  • Dates for Special Election Periods vary.
  • If you qualify for and miss your Special Enrollment Period you will need to wait for one of the other enrollment periods.

Medicare Advantage Open Enrollment Period

  • Each year, from January 1 to March 31.
  • Anyone currently enrolled in a Medicare Advantage plan can switch or drop their plan.
  • Benefits begin the first of the month.
  • The Annual Election Period (AEP) soon follows, from October 15 to December 7.

Do I have to enroll in Medicare Advantage every year?

You will be automatically re-enrolled in your Medicare Advantage plan annually – unless your insurer no longer provides the plan or you choose to switch plans. Then you can shop for a different plan during the Annual Enrollment Period.

How do I enroll in a Medicare Advantage plan?

We can help you find the right Medicare Advantage plan for your lifestyle and budget. We have tools to help you search for plans based on what’s important to you. Answer a few quick questions and we’ll provide a recommendation on the Medicare plan that matches you best. You can compare our Medicare Advantage HMO, Medicare Advantage PPO and other plans based on benefits, costs, quality, prescription drug coverage, and doctors. You can save your favorites and come back during one of the enrollment periods to apply.

Learn more about our Medicare Advantage HMO plans and our Medicare Advantage PPO plans.

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Y0114_21_3000539_I_C CMS Accepted (07/17/2021)

Benefits, premiums, copays and plans may vary by county. Medicare Advantage plans may not be available in all counties.

Anthem Blue Cross is a Medicare Advantage plan with a Medicare contract. Enrollment in Anthem Blue Cross depends on contract renewal.

This information is not a complete description of benefits. Contact the plan for more information. Limitations, copayments, and restrictions may apply. Benefits, premiums and/or co-payments/co-insurance may change on January 1 of each year. You must continue to pay your Medicare Part B premium. The provider network may change at any time. You wll receive notice when necessary.

Anthem Blue Cross is the trade name of Blue Cross of California. Independent licensee of the Blue Cross Association. ANTHEM is a registered trademark of Anthem Insurance Companies, Inc. The Blue Cross name and symbol are registered marks of the Blue Cross Association. The SilverSneakers® Fitness Program is provided by Healthways, Inc., an independent company. Healthways and SilverSneakers® are registered trademarks of Healthways, Inc. and/or its subsidiaries.

For Dual-Eligible Special Needs Plans: This plan is available to anyone who has both Medical Assistance from the State and Medicare.

This information is not a complete description of benefits. Call Customer Service, (TTY:711) for more information.

Attention: If you speak any language other than English, language assistance services, free of charge, are available to you. Call our Customer Service number, (TTY: 711). ATENCIÓN: Si habla español, tiene a su disposición servicios gratuitos de asistencia lingüística. Llame a nuestro número de Servicio de Atención al Cliente (TTY: 711). 注意:如果您使用非英語的其他語言,您可以免費獲得語言援助服務。請致電聯絡客戶服務部(聽語障用戶請致電:711)。