What Does Medigap Cover? Benefits by Plan Type

Medicare Supplement insurance, also called Medigap, is private coverage you add to Original Medicare to pay the cost-sharing it leaves to you. Original Medicare has no yearly cap on those costs, and a single hospital stay costs you $1,736 before Medicare pays anything.

The federal government standardizes all 10 plan types, so Plan G from Aetna covers the same benefits as Plan G from UnitedHealthcare in every state that uses standard plan letters. Price is where they differ. In MoneyGeek’s analysis of 2026 Medigap rates, Plan G for a 65-year-old averages $144 a month with Aetna and $358 with UnitedHealthcare.

Medigap pays the cost-sharing Original Medicare assigns to you after Medicare processes a claim and pays its share. Every plan covers Part A coinsurance and hospital costs. Coverage for Part B coinsurance, skilled nursing care, the $1,736 Part A deductible and Part B excess charges depends on the plan letter.

No Medigap plan covers prescription drugs. You'll need a separate Medicare Part D plan for drug coverage, an exclusion that has applied since 2006. Dental, vision, hearing aids, private-duty nursing and long-term custodial care are also excluded from all 10 standardized plans.

At age 65, Medigap premiums range from $61 a month for high-deductible Plan G to $294 for Plan C, and the average across all plans is $189, based on MoneyGeek’s rate data. Insurers that use attained-age pricing raise your premium as you get older. Plan G priced this way averages $220 a month at 65 and $279 at 75, which adds $708 a year.   

Location changes the price of identical coverage too. Plan G at 65 averages $169 a month in South Carolina and $483 in New York.

*Figures are national average monthly premiums for nonsmokers, from 16,954 Medicare.gov quotes MoneyGeek collected in November 2025 for the 2026 plan year. Plans C and F are sold only to people who became eligible for Medicare before January 1, 2020.   

Plan B averages $257 a month at 65, which is $32 more than Plan D and $37 more than Plan G, even though D and G add skilled nursing and foreign travel coverage. Plan A covers only core benefits and still costs more than Plans L, M and N. Federal rules standardize Medigap benefits, but each insurer sets its own prices, so compare plans by benefits first and price second.

Except in New York and in specific guaranteed-issue situations, your six-month Medigap Open Enrollment Period is the only window when insurers must accept you at standard rates regardless of health. If you wait until a health problem forces the decision, an insurer can charge you more or turn you down.

Medigap and Medicare Advantage solve the same problem in opposite ways. Medigap works alongside Original Medicare. You see any provider who accepts Medicare and the plan pays your cost-sharing. Medicare Advantage is a private plan you get instead of Original Medicare, and it uses an HMO or PPO provider network.

CMS estimates the average Medicare Advantage premium at $14 a month in 2026. Those plans come with network restrictions and prior authorization requirements, and you still pay the $202.90 monthly Part B premium with either option. If you have chronic conditions or see specialists regularly, provider freedom outweighs the premium savings. A healthy buyer on a fixed income often finds the lower premium more practical.

Medigap is the right choice for enrollees who want predictable costs and the freedom to see any provider that accepts Medicare. Medicare Advantage is the better fit for buyers who want the lowest monthly premium and don’t mind using a network.

The right Medigap plan depends on how often you use health care, whether your providers accept Medicare assignment (meaning they bill no more than Medicare's approved rate) and how much premium certainty you need.

Plan G is the most comprehensive option available to new Medicare enrollees. It covers Part B excess charges, skilled nursing costs and the full Part A deductible. Only the $283 annual Part B deductible falls to you.

Plan N averages $171 a month at 65, $49 less than Plan G, per MoneyGeek’s data. You pay copays of up to $20 for some office visits and up to $50 for ER visits that don’t result in an inpatient admission, and Plan N doesn’t cover Part B excess charges.

Plans K and L suit buyers who want lower monthly costs and can absorb a defined share of each bill. Plan K’s out-of-pocket cap is $8,000 in 2026 and Plan L’s cap is $4,000. High-deductible Plan G has the lowest premium at $61 a month, and you pay up to $2,950 in covered costs before it pays.