Explore California’s Medicare Supplement (aka Medigap) plans and learn how to enroll

Like most insurance coverage, Original Medicare doesn’t cover all of your healthcare costs. It generally covers 80% of your medical bills once you’ve met your deductible, leaving you responsible for the remaining 20%. It’s important for Medicare beneficiaries to understand their options for Medicare Supplement plans, which help cover the out-of-pocket costs that Original Medicare (Part A and Part B) doesn’t not cover. These costs include copayments, coinsurance, and deductibles.

You can choose from nine different Medicare Supplement plans in California. Each plan type covers a different set of out-of-pocket costs. Plans F, G, and N are the most popular because they almost eliminate your out-of-pocket costs and have reasonable premiums. 

Note: Plans F and C are unavailable for Medicare enrollees who turn 65 after January 1, 2020.

Key Takeaways:

  • You can choose from nine different Medicare Supplement plans in California. They are labeled by letters A-N. Plans F and G also have a high-deductible option.

  • Most states have one additional Medicare Supplement plan: Plan M.

  • Among new Medicare enrollees, Medicare Supplement Plans N and G are the most popular.

  • Each Medigap policy will have different pricing based on the plan type, personal factors, and pricing structures chosen by the insurance carrier.

  • Our California Medicare guide has information on how to enroll, plan comparisons, and tips on saving money on insurance plans.

Comparing Medicare Supplement plans

Also called Medigap, Medicare Supplement plans help cover the "gaps" left over from Original Medicare coverage. There are ten types of Medicare Supplement plans that most Medicare beneficiaries can choose from and two high-deductible options for Medigap Plan G and Medigap Plan F. California has most of the same Medigap plans as most states, but does not offer a Medigap Plan M. Wisconsin, Massachusetts, and Minnesota have their own options for Medigap plans..

All Medigap plans are labeled with a letter to distinguish them from one another. You’ll find the following plan types available in California:

  • Medigap Plan A

  • Medigap Plan B

  • Medigap Plan C

  • Medigap Plan D

  • Medigap Plan F

  • Medigap Plan F-high deductible

  • Medigap Plan G

  • Medigap Plan G-high deductible

  • Medigap Plan K

  • Medigap Plan L

  • Medigap Plan N

Each plan provides a different set of coverage for out-of-pocket costs. For example, Plans K and L cover a percentage of certain benefits and have an out-of-pocket spending limit while the rest of the Medicare Supplement plans fully cover certain out-of-pocket costs and therefore don’t have a maximum spending limit. Take a peek at our Medigap comparison chart for more plan details. 

Every plan of the same letter will cover the same costs, but what you pay for the plan may be different from what your neighbor pays. This is because Medigap pricing depends on a variety of personal factors and insurance carrier pricing structures. For instance, all Plan Gs provide the same cost coverage, but what you pay specifically depends on things like where you live and which policy you choose. We explain pricing in more detail below. 

How much does a Medigap plan cost in California?

Medigap plans have premiums that you’ll pay each month. These monthly premiums range from $30/mo for a high-deductible Plan G to $944/mo for the highest cost Medigap Plan G in California. To get a sense of California’s Medicare Supplement plan cost-breakdown, use Medicare.gov’s plan comparison tool.

Insurance carriers determine the price of Medigap plans by assessing economic and personal factors. Here are the personal factors that could influence your Medicare Supplement premium:

  • Your age

  • Your gender

  • Your location

  • Whether or not you are a tobacco smoker

  • Household discounts available with some Medigap plans

In addition to these personal factors, the pricing of your Medicare Supplement premium also involves carrier pricing structures and economic factors, like inflation. We'll explain how the Medigap pricing structures work below.

Medigap plan pricing structures

There are three different ways that insurance providers price Medicare Supplement plans. Your plan can be community-rated, issue-age-rated, or attained-age-rated. These pricing structures determine how your policy’s premiums can change over time. 

Community-rated (or no age-rated)

With a community-rated Medigap policy, all policyholders pay the same monthly premium, regardless of their age. This pricing structure doesn’t change over time, meaning you won’t pay more for your premium as you age. However, your premium may be higher or lower based on where you live. Plans with this pricing structure are less common in California.

Issue-age-rated (or entry age-rated)

An issue-age-rated Medigap policy sets your premium based on your age when you purchase the plan. Your monthly premium is tied to the age you were/are upon enrollment. This means that the younger you are when you first enroll, the lower your premiums will be. Issue-age-rated plans can’t increase your premiums as you age.


Attained-age-rated Medigap policies set premiums based on your current (attained) age. You’ll have lower premiums when you first enroll, but costs will gradually increase over time as you age.

What is the best Medicare Supplement plan in California?

Most Medicare beneficiaries consider Plan G to be the best Medicare Supplement plan. Medigap Plan G provides coverage for every out-of-pocket cost except for the Medicare Part B deductible. 

That being said, there isn’t one “best” Medicare Supplement plan in California. While Plan G tends to be the most cost-effective with the highest level of coverage, the right plan for you depends on your healthcare and financial needs. 

How to enroll in the best California Medicare Supplement plan

The best time to sign up for a Medigap plan is during the first six months after you get Medicare Part B. This is your Medigap Open Enrollment Period. During this time, insurance companies have to accept your application without asking about your health. If you wait until after this window of time, providers can reject your application based on your answers to health questions or charge you more for the policy. 

Switching Medigap plans in California

California is one of a handful of states with a Medigap Birthday Rule. This rule allows current Medigap plan holders to switch to another Medigap plan each year during the 60 days following their birthday. If Medigap plan holders choose to switch to a plan with equal or lesser benefits compared to their existing policy (e.g., from Medigap Plan G to Plan N), insurance companies cannot ask health history questions or establish a coverage waiting period. 

Choosing the right Medicare Supplement plan can be confusing, but our California Medicare Advisors are here to help at no cost to you. An Advisor can give you personalized advice that works with your healthcare needs and budget. Schedule a chat, or call us at (855) 900-2427 to get the best and most cost-effective insurance for you.

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