Medicare Supplement Plan G Explained: Is It the Right Choice for Your Parent?

If you are helping a parent choose a Medicare supplement policy for the first time, you have probably encountered Plan G. It appears at the top of most comparison charts, comes with higher monthly premiums than other options, and is frequently described as "the gold standard" of Medigap coverage. That reputation is earned — but understanding exactly why helps you decide whether it is the right match for your parent's situation.

What Plan G Covers

Medigap (also called Medicare Supplement) policies are sold by private insurance companies to wrap around Original Medicare and cover the costs Medicare does not pay. All Medigap plans are standardized by the federal government, which means a Plan G from one insurer covers exactly the same benefits as a Plan G from any other insurer. You are only shopping for price and customer service when comparing Plan G across carriers.

Plan G covers:

• Part A coinsurance and hospital costs — up to 365 days after Medicare benefits are exhausted
• Part B coinsurance — the 20% that Original Medicare leaves behind on all covered services
• Part A hospice care coinsurance
• Skilled nursing facility care coinsurance — for days 21 through 100 of a covered SNF stay
• Part A deductible — the per-benefit-period hospital deductible (approximately $1,676 in 2026)
• Part B excess charges — the up-to-15% surcharge that non-participating physicians can bill above the Medicare-approved rate
• Foreign travel emergency — 80% of emergency care costs outside the US, up to plan limits

The one cost Plan G does not cover is the Part B annual deductible, which is $257 in 2026. After your parent pays that amount for the year, Plan G covers 100% of all remaining Medicare-approved costs. No copays for office visits. No coinsurance for surgeries. No daily charges for hospital stays.

What Plan F Was — and Why It Matters Now

Until January 1, 2020, Plan F was the most popular Medigap plan because it covered the Part B deductible in addition to everything Plan G covers. Congress closed Plan F to new enrollees in 2020 to discourage overutilization of healthcare.

Seniors who purchased Plan F before 2020 can keep it. However, since no new, younger members can join the Plan F risk pool, existing Plan F policyholders face a "premium death spiral" — as the pool ages and becomes sicker, premiums rise faster than inflation. If your parent is currently on Plan F, it is worth comparing their current premium against a new Plan G policy. The savings from switching often exceed the $257 deductible they would take on.

For anyone enrolling in Medicare for the first time today, Plan G is the most comprehensive option available.

How Plan G Compares to Plan N

The main alternative to Plan G is Plan N, which typically runs $30 to $60 per month less in premium. The trade-off is a modest amount of cost-sharing:

• Up to $20 copay for some office visits
• Up to $50 copay for emergency room visits that do not result in inpatient admission
• No coverage for Part B excess charges — if your parent sees a non-participating physician, they could owe up to 15% above the Medicare rate

Plan N makes sense for healthier seniors who visit the doctor infrequently and live in states that ban excess charges. States including New York, Connecticut, Pennsylvania, Ohio, Massachusetts, and Minnesota prohibit physicians from billing above the Medicare-approved amount. In those states, Plan N provides nearly identical financial protection to Plan G at a meaningfully lower premium.

In states where excess charges are permitted, Plan G is the safer choice for parents who see specialists regularly or may need to see physicians outside their immediate area.

What Plan G Costs

Because the benefits are standardized, all price variation between carriers is driven by the insurer's pricing methodology, administrative efficiency, and market.

Monthly Plan G premiums vary by:

• Age at enrollment — most policies cost more as you age
• State and county — markets with more competition tend to have lower premiums
• Pricing method — this is the most important factor most families overlook

Medigap insurers use one of three pricing structures:

1. Attained-age rated — premiums increase every year as your parent ages. They start low but can become very expensive by age 80 or 85.
2. Issue-age rated — premiums are set based on the age at purchase and do not increase solely because your parent gets older (though inflation adjustments still apply). Cheaper over the long run.
3. Community rated — everyone in the area pays the same premium regardless of age. Available primarily in states like New York, Connecticut, and Massachusetts.

When comparing Plan G quotes, always ask which pricing method each carrier uses. A low premium from an attained-age carrier may become the most expensive option within five to ten years.

The Guaranteed Issue Window — Why Timing Matters

Here is the single most important fact about buying Medigap: your parent has a protected window during which no insurer can deny them coverage or charge more due to health conditions. This is called Guaranteed Issue.

The Medigap Open Enrollment Period is a six-month window that begins the month your parent's Part B coverage becomes effective. During this window, they can buy any Plan G (or any other Medigap plan) from any insurer in their state, and the insurer must accept them at the standard rate regardless of pre-existing conditions.

Once this window closes, insurers in most states can use medical underwriting — they can deny coverage, exclude conditions, or charge significantly higher premiums based on your parent's health history. Waiting until a parent has been diagnosed with diabetes, heart disease, or cancer before buying Medigap often means being denied or facing unaffordable rates.

The message for adult children: if your parent is approaching 65, securing a Plan G policy during the six-month guaranteed issue window is one of the most important financial moves you can make on their behalf.

Plan G in High-Cost States Like California

California is worth addressing specifically because it generates significant search volume around this question. California uses attained-age rating as the standard Medigap pricing method, and the state is also home to a large number of carriers competing for enrollees.

California does not have a birthday rule that allows penalty-free Medigap switching, unlike states such as Oregon, Idaho, Nevada, Louisiana, and Maryland. This means that once your parent's guaranteed issue window closes in California, switching Plan G carriers involves underwriting — they would need to qualify medically.

The practical implication: in California, getting quotes from multiple carriers during the guaranteed issue window is especially important, because you are choosing a carrier you may be staying with for a long time. Prioritize issue-age rated carriers to avoid accelerating premium increases.

When Plan G May Not Be the Right Choice

Plan G is not the right fit for every parent:

• If your parent qualifies for a Medicare Savings Program (due to limited income), those programs may cover Part B premiums and cost-sharing, making a Medigap supplement redundant.
• If your parent qualifies for Extra Help (Low Income Subsidy) for Part D, the overall cost structure changes and a Medicare Advantage plan with bundled drug coverage may actually be more advantageous.
• If your parent is in excellent health and very cost-conscious, Plan N offers a meaningful premium reduction with manageable risk for the right profile.

How to Choose a Plan G Carrier

All Plan G policies cover the same services, so the comparison is purely financial and practical:

1. Get quotes from at least three to five carriers. Use tools at medicare.gov or work with an independent broker (not a captive agent tied to one insurer).
2. Identify each carrier's pricing method (attained-age, issue-age, or community-rated).
3. Check the carrier's financial stability rating (A.M. Best A or better is the standard benchmark).
4. Check customer service reviews — claims processing and responsiveness matter more than they seem when your parent is dealing with a health event.

Choosing between Plan G, Plan N, and Medicare Advantage is the most consequential Medicare decision your parent will make. The Medicare Enrollment Guide walks adult children step by step through how to compare total annual costs, evaluate each option against your parent's health profile, and lock in coverage before the guaranteed issue window closes. Get the Medicare Enrollment Guide and make this decision with a clear framework.