Medicare Supplement

Medigap in Irvine: the plan letters California sells and the rules behind them

IRVINE, Calif. — If you have Original Medicare and you live in Irvine, a Medicare Supplement policy — better known as Medigap — is the extra coverage that helps pay the deductibles, copays and coinsurance Medicare leaves behind. The policies sold here follow a federal template, so the letter on the plan tells you what it covers. What changes from company to company is the price and the customer service, not the benefits inside a given letter.

Medicare SupplementIrvine, CA

Here is a plain-English look at which Medigap letters a person newly eligible for Medicare can buy in California, how Medigap fits with Part D drug coverage, and where to check prices and state rules before you sign anything.

What Medigap is, and what it is not

Medigap is private insurance that pairs with Original Medicare — Part A (hospital) and Part B (doctor and outpatient). After Medicare pays its share of a covered service, your Medigap policy picks up some or all of what is left, depending on the letter you chose.

A few things Medigap is not:

• It is not a Medicare Advantage plan. You cannot have both at the same time.
• It does not include prescription drug coverage. For that, you add a stand-alone Part D plan.
• It is not dental, vision or hearing coverage.

Because Medigap only rides along with Original Medicare, the choice really starts with the question of whether you want Original Medicare plus Medigap plus Part D, or a Medicare Advantage plan instead.

The plan letters you can buy in California today

Medigap plans are standardized by the federal government in most states, including California. That means Plan G from one company covers the same Medicare cost-sharing as Plan G from any other company licensed in the state.

For people newly eligible for Medicare today, these are the standardized letters available in California:

• Plan A
• Plan B
• Plan D
• Plan G
• Plan G high-deductible (Plan G-HD)
• Plan K
• Plan L
• Plan M
• Plan N

Plans C and F still exist, but only for people who became eligible for Medicare before Jan. 1, 2020. If that is you, you may still be able to buy or keep one; if you turned 65 after that date, those two letters are closed to you.

Three states — Massachusetts, Minnesota and Wisconsin — standardize Medigap differently. California uses the federal letters, so what you read on Medicare.gov about Plan G or Plan N applies here.

How Medigap and Part D fit together

If you go the Original Medicare + Medigap route, you will usually want to add a Part D drug plan on the same day your coverage starts. A few things to keep in mind for 2026:

• Part D has a $2,100 annual out-of-pocket cap for covered drugs.
• The maximum Part D deductible any plan can charge is $615.
• The old "donut hole" coverage gap is gone as of 2025; Part D now has three phases.
• The Medicare Prescription Payment Plan lets you spread your drug costs across the year in monthly installments instead of paying big amounts at the pharmacy counter.
• Higher-income enrollees pay an IRMAA surcharge on Part B and Part D; for a single filer in 2026, IRMAA begins above $109,000 in income.

Medigap does not change any of that — Part D is its own decision.

California rules that shape your choice

California is a "community-rated" and "issue-age-rated" and "attained-age-rated" state depending on the insurer, meaning companies can use different methods to set the premium for the same lettered plan. Two policies that look identical on paper can be priced very differently and can rise at different speeds as you age. Before you buy, ask the company which pricing method it uses.

California also has a "birthday rule." Each year, around your birthday, you have a limited window to switch to another Medigap policy of equal or lesser benefits without medical underwriting. The exact length of the window and how it works can change, so confirm the current rule with the California Department of Insurance or your local SHIP counselor before you rely on it.

Outside of your initial six-month Medigap open enrollment period at 65 (or when you first enroll in Part B), and outside of a federal or state guaranteed-issue situation, insurers in California can generally use health questions to decide whether to sell you a policy and at what price. That is why timing matters.

How to compare policies without an insurer's sales pitch

Because no insurer list is included with this article, here is how to build your own short list for Irvine, which sits in Orange County:

• Medicare.gov's Medigap policy search lets you enter your Irvine ZIP code and see every company licensed to sell each plan letter in your area, along with sample premiums.
• The California Department of Insurance publishes a Medigap rate guide that shows how companies price each letter for your age.
• California's State Health Insurance Assistance Program — known here as HICAP — gives free, unbiased counseling by phone or in person. HICAP counselors do not sell insurance.

The table below lists every plan letter available to newly eligible enrollees in California, so you can see at a glance which letters to compare.