What Is Medigap?
Medigap (Medicare Supplement Insurance) is private insurance that covers cost-sharing under Original Medicare — deductibles, coinsurance, and copayments that would otherwise come out of your pocket. Because Original Medicare has no annual out-of-pocket maximum, a single hospital stay or serious illness can generate tens of thousands of dollars in costs. Medigap eliminates or greatly reduces that exposure.
Important: Medigap only works with Original Medicare. If you have a Medicare Advantage plan, you cannot purchase or use a Medigap policy.
Standardized Plan Letters
Medigap plans are standardized by the federal government and labeled with letters. Every Plan G from every insurer covers the same benefits — only the premiums and customer service differ. The available plans (in most states) are A, B, D, G, K, L, M, and N. Plans C and F are no longer available to people who became newly eligible for Medicare on or after January 1, 2020.
Plan Comparison Table
| Benefit | Plan G | Plan N | Plan K | Plan L |
|---|---|---|---|---|
| Part A coinsurance (days 61–90) | 100% | 100% | 100% | 100% |
| Part A hospital deductible | 100% | 100% | 50% | 75% |
| Skilled nursing coinsurance | 100% | 100% | 50% | 75% |
| Part B deductible ($264 in 2026) | Not covered | Not covered | Not covered | Not covered |
| Part B excess charges | 100% | Not covered | Not covered | Not covered |
| Part B copay/coinsurance | 100% | 100% (with up to $20 office / $50 ER copays) | 50% | 75% |
| Foreign travel emergency | 80% | 80% | Not covered | Not covered |
| Annual OOP limit | None needed | None (copays apply) | $7,060 | $3,530 |
Plan G: The Gold Standard
Plan G is the most comprehensive Medigap policy available to new enrollees. It covers all Original Medicare cost-sharing except the annual Part B deductible ($264 in 2026). Once you pay that deductible, your out-of-pocket costs for Medicare-covered services are effectively zero for the rest of the year.
Monthly premiums for Plan G typically range from $120 to $350 depending on your age, gender, tobacco use, and state. Compare rates in your state to find the lowest cost for identical coverage.
Who should pick Plan G?
- People with chronic conditions who see doctors frequently
- Anyone who wants maximum financial predictability
- Beneficiaries who travel and want foreign emergency coverage
- Those who can afford the premium and want peace of mind
Plan N: The Budget-Friendly Alternative
Plan N is identical to Plan G except for two differences: it does not cover Part B excess charges, and it applies small copays — up to $20 for some office visits and up to $50 for emergency room visits that do not result in an inpatient admission. In exchange, Plan N premiums are typically $30–$80 less per month than Plan G.
Who should pick Plan N?
- Healthy beneficiaries who visit the doctor infrequently
- Those comfortable with small, predictable copays
- People in states where few providers charge excess fees
- Budget-conscious enrollees looking for solid protection at lower cost
Plans K and L: High-Deductible Options
Plans K and L cover a percentage of costs (50% and 75% respectively) rather than 100%, but they come with annual out-of-pocket limits — $7,060 for Plan K and $3,530 for Plan L in 2026. Once you hit those limits, the plan covers 100%. These are useful for people who want catastrophic protection at the lowest possible premium.
When to Buy Medigap
The single most important rule: enroll during your Medigap Open Enrollment Period, which is the 6-month window starting the month you are both age 65 or older and enrolled in Part B. During this window, insurers must sell you any Medigap plan at the best rate regardless of health status — no medical underwriting, no pre-existing condition exclusions.
After this window closes, most states allow insurers to deny coverage or charge more based on health conditions. Certain states — Connecticut, Massachusetts, and New York — guarantee open enrollment year-round, but those are exceptions. Timing your enrollment is crucial.
Medigap Pricing Methods
Insurers use one of three pricing approaches, which significantly affects how your premium grows over time:
- Community-rated — Same premium regardless of age. Best long-term value.
- Issue-age-rated — Premium based on age at purchase; does not increase with age (but may increase for inflation).
- Attained-age-rated — Premium increases as you age. Cheapest initially, most expensive over time.
Compare pricing methodology as well as current rates. A community-rated plan at $180/month will almost certainly be cheaper than an attained-age plan starting at $130/month after 10 years. Use tools on our Medigap enrollment page to compare in your area.