Key takeaways
- California offers a range of Medicare options, including Original Medicare (Parts A and B), Medicare Advantage (Part C), Medicare Part D for prescription drugs, and Medicare Supplement (Medigap) insurance.
- While Original Medicare plans are consistent nationwide, Medicare Advantage, Part D, and Medigap plans can vary by location. Therefore, Californians should use the Medicare online tool to find plans available in their specific area.
- For additional help with Medicare questions, Californians can contact HICAP (Health Insurance Counseling & Advocacy Program) or Medicare directly.
Medicare is a health insurance program for people 65 and older, as well as people of any age who have certain health conditions and disabilities.
It is made up of four parts:
- Part A (hospital insurance) and Part B (medical insurance) are known as Original Medicare
- Part C, also known as Medicare Advantage, is an alternative to Original Medicare
- Part D, which is prescription drug coverage
Individuals can also purchase a supplement insurance plan (Medigap) to help cover certain out-of-pocket costs associated with Original Medicare.
Snapshot of Medicare in California
The Centers for Medicare & Medicaid Services (CMS) reported the following information on Medicare trends in California for the 2026 plan year:
- A total of 7,050,213 residents of California were enrolled in Medicare.
- The average monthly Medicare Advantage plan premium changed from $12.61 in 2025 to $13.99 in 2026.
- There are 402 Medicare Advantage plans available in California for 2026, compared with 421 plans in 2025.
- Around 99.89% of Californiaresidents with Medicare have access to buy a Medicare Advantage plan, with 99.64% having access to a $0 premium.
- In 2026, 12 stand-alone Medicare Part D plans are available in California, and the lowest monthly premium for a stand-alone Part D plan is $0.
- 32.57% of people with a stand-alone Part D plan get Extra Help.
- As in most states, 10 different Medigap plans are offered in California in 2026.
Medicare is more than just one part. Different plans and components cover various aspects of individual healthcare.
- Original Medicare: Original Medicare is managed by the federal government and includes two main parts: Part A (hospital insurance) and Part B (medical insurance). Neither part covers prescription drugs.
- Medicare Advantage (Part C): Medicare Advantage plans are provided by Medicare-approved private insurance companies and offer the same benefits as Original Medicare. They may also cover benefits like vision, dental, or prescription drugs. Some plans have limited provider networks, so people may wish to confirm their doctors and facilities are in-network before enrolling.
- Medicare Part D: Medicare Part D is also offered by Medicare-approved private insurance companies and provides coverage for prescription drugs. If an individual has Original Medicare, they can purchase a stand-alone Part D plan. If a person has a Medicare Advantage plan without prescription drug coverage, they can speak with their insurer to verify if they can purchase a stand-alone Part D plan.
- Medicare supplement (Medigap): Medigap plans help cover some of the costs associated with Original Medicare coverage, which might include copays and coinsurance. Medigap plans are standardized in most states, and individuals can choose among 10 plans to supplement Original Medicare. People cannot use Medigap with Medicare Advantage.
For all private Medicare options, availability varies by county, so individuals can check Medicare.gov for what’s available in their area.
Individuals who live in California can qualify for Medicare at age 65 if they’re a U.S. citizen or legal resident for at least 5 years. If a person is under 65 years, they may also qualify through disability or by living with end stage renal disease (ESRD) or amyotrophic lateral sclerosis (ALS).
When choosing a plan, consider provider networks, costs, and quality ratings. Individuals may be able to join a plan or modify their coverage during one or more of the following enrollment periods:
- Initial enrollment: Enroll 3 months before to 3 months after the month of a person’s 65th birthday.
- Open enrollment: Join or change plans from October 15 to December 7.
- Medicare Advantage open enrollment: Switch Medicare Advantage plans or return to Original Medicare from January 1 to March 31 if a person already has Medicare Advantage.
- Special enrollment period: Enroll after a life change, such as losing job-based coverage.
If an individual is eligible for Medicare due to a disability, they will be automatically enrolled. If a person is eligible based on age, they will need to enroll themselves.
The following resources in [State] can help individuals make the best Medicare decisions for their circumstances:
- California Health Insurance Counseling and Advocacy Program (HICAP) at 800-434-0222
- Medicare at 800-633-4227 (TTY: 877-486-2048)
Medicare resources
For more resources to help guide you through the complex world of medical insurance, visit our Medicare hub.
Various Medicare options are available in California: Original Medicare (parts A and B), Medicare Advantage (Part C), Medicare Part D, and Medigap.
Original Medicare plans are national. However, Medicare Advantage, Part D, and Medigap plans can vary by area. A person can find plans that are available in their area by using the Medicare online tool.
For questions about Medicare, people can contact HICAP or Medicare.