Why Medigap Exists
Original Medicare Parts A and B are excellent coverage — but they were never designed to be your only coverage. Part B pays 80% of approved outpatient medical costs after your deductible. The remaining 20% is your responsibility. With no annual out-of-pocket maximum, a serious illness — cancer treatment, cardiac surgery, a major accident — could leave you with tens of thousands of dollars in personal costs. Medigap was created to fill that gap.
Medigap plans are sold by private insurance companies and are standardized by the federal government. That means a Plan G from one insurer covers the exact same benefits as a Plan G from any other insurer. The only difference between companies is the premium and the service quality — making comparison shopping straightforward.
The Most Popular Plans — G and N
Plan G — Most Comprehensive
Covers the Part B deductible once paid, then pays 100% of Part B coinsurance, all Part A coinsurance and hospital costs, skilled nursing facility coinsurance, Part A hospice care coinsurance, and foreign travel emergency care. Plan G is the most comprehensive plan available to new Medicare enrollees and is the most popular choice for people who want maximum predictability.
Plan N — Lower Premium Option
Covers most of the same gaps as Plan G but requires small copays of up to $20 for office visits and up to $50 for emergency room visits. Plan N premiums are typically lower than Plan G, making it a good fit for people who are generally healthy and willing to pay modest copays in exchange for lower monthly costs.
Note on Plan F: Plan F was the most comprehensive Medigap option and covered the Part B deductible entirely. However, Plan F is no longer available to people who became newly eligible for Medicare on or after January 1, 2020. If you became eligible before that date, you may still be able to enroll in Plan F.
The Guaranteed Acceptance Window — Do Not Miss This
When you first enroll in Medicare Part B, you have a 6-month Medigap Open Enrollment Period. During this window, every insurance company that sells Medigap in your state must sell you any plan they offer — at their standard rates — regardless of your health history. No medical underwriting. No exclusions for pre-existing conditions. No denials.
After this window closes, insurers in most states can use medical underwriting. A diabetes diagnosis, a history of cancer, heart disease, or dozens of other conditions can result in higher premiums, coverage exclusions, or outright denial. This window does not reopen unless you qualify for a specific Special Enrollment Period.
The window closes permanently: Many people delay Medigap enrollment thinking they will wait until they actually need it. By then, they may be medically ineligible. The best time to enroll in Medigap is during those first 6 months — before any health issues can affect your eligibility.
Medigap and Prescription Drugs
Medigap plans do not include prescription drug coverage. If you have Original Medicare plus a Medigap plan, you will need a separate Part D prescription drug plan to cover your medications. A local agent can help you coordinate a Medigap and Part D combination that covers your specific prescriptions at the lowest total cost.
Medigap vs. Medicare Advantage — Choosing Between Them
This is the central decision for most new Medicare enrollees. Medigap offers maximum flexibility — see any Medicare provider in the country — and predictable costs. Medicare Advantage offers lower premiums, often includes dental and vision, but restricts you to a provider network. There is no universally right answer. Your health, your providers, your travel habits, and your financial situation all factor in. A licensed independent agent can model both options with your actual doctors and prescriptions.