California has one of the largest Medicare populations in the United States. More than 7 million residents are enrolled in Medicare, and many choose Medicare Supplement plans, also called Medigap, to help cover out-of-pocket costs.
Medigap plans work alongside Original Medicare. They help pay for deductibles, copayments, and coinsurance.
These plans are standardized, which means the benefits are the same across insurers, but prices can vary widely depending on the company and your location.
Medicare Supplement Plans in California
Medicare Supplement plans are private insurance policies designed to fill coverage gaps in Original Medicare. They do not replace Medicare but work with it.
Calculate Your 2026 COLA Increase →In California, there are up to 10 standardized Medigap plans available, labeled A through N. Not all plans are available to new enrollees. For example, Plan F and Plan C are no longer open to people who became eligible after 2020.
These plans allow you to visit any provider that accepts Medicare, without needing referrals or network restrictions. This flexibility is one reason many seniors prefer Medigap over Medicare Advantage.
How Much Do California Medigap Plans Cost in 2026?
Costs for Medicare Supplement plans in California vary based on age, location, and insurer. For 2026, the average monthly premium for a 65-year-old is around $200.
Premiums typically range from:
- About $106 to $272 per month depending on the plan
- Around $168 for Plan N on average
- About $224 for Plan G
- Up to $272 for Plan F, which offers the most coverage
Other estimates show that the national average Medigap premium is about $149 to $189 per month at age 65, but California tends to be slightly higher due to healthcare costs in the state.
Your actual premium will depend on your ZIP code, gender, tobacco use, and the pricing method used by the insurer.
Which Medigap Plans Are Most Popular in California?
Most California residents choose a small group of plans. The most popular options include:
- Plan G
- Plan N
- Plan F (for those eligible before 2020)
Plan G is now the top choice for new enrollees because it offers broad coverage with lower premiums than Plan F. Plan N is a lower-cost option but includes some copayments.
Together, these plans account for the majority of Medigap enrollments in the state.
How Do Rates Vary Across California?
Medigap rates can differ significantly depending on where you live. For example, Plan G premiums for a 65-year-old in California may look like:
- Around $164 per month in Sacramento
- About $205 per month in Los Angeles
- Around $173 per month in Sonoma County
This variation is due to local healthcare costs and competition among insurers. Even within the same plan type, two companies may charge very different premiums for identical coverage.
What Factors Affect 2026 Medigap Rates?
Several key factors influence your premium in 2026:
- Age at enrollment
- Location within California
- Tobacco use
- Gender
- Pricing model used by the insurer
There are three main pricing methods:
- Community-rated plans charge the same premium to everyone
- Issue-age-rated plans base premiums on your age when you enroll
- Attained-age-rated plans increase premiums as you get older
Understanding these models is important because they affect long-term costs, not just your starting premium.
Which Companies Offer Medigap Plans in California?
Many insurance companies offer Medicare Supplement plans in California. The largest providers include:
Since benefits are standardized, the main differences between companies are price, customer service, and rate stability over time.
When Can You Enroll in a Medicare Supplement Plan?
The best time to enroll is during your Medigap Open Enrollment Period. This is a six-month window that starts when you are 65 or older and enrolled in Medicare Part B.
During this period:
- You cannot be denied coverage
- You pay standard rates regardless of health
- You avoid medical underwriting
Outside this window, insurers may charge higher premiums or deny coverage based on health history.
