Medigap.
In plain English
Medigap, also called Medicare Supplement Insurance, is a private policy that fills the gaps in Original Medicare. Original Medicare pays most of your bills but leaves you responsible for deductibles, copays, and that 20 percent coinsurance on many Part B services, which has no cap. A Medigap policy picks up some or all of those leftover costs depending on which lettered plan you buy. Medigap plans are standardized, so a Plan G from one company covers the same things as a Plan G from another, and they only work with Original Medicare, not with Medicare Advantage.
01Why it matters
Original Medicare has no yearly out-of-pocket maximum, so one serious illness could leave you owing thousands in coinsurance. Buying Medigap during your one-time guaranteed-issue window matters because after it closes, an insurer can charge you more or turn you down for health reasons.
02The math, step by step
Say you have a hospital procedure and surgeon visits that leave you owing $4,000 in Medicare deductibles and the 20 percent coinsurance. With a Medigap Plan G, the policy would pay nearly all of that after your Part B deductible, so your out-of-pocket cost stays small and predictable. Monthly Medigap premiums vary by plan letter, insurer, age, and location, so compare quotes for the plans sold where you live.
03What this is NOT
Medigap is not an alternative to Medicare; it sits on top of Original Medicare to reduce your costs. You cannot use a Medigap policy with a Medicare Advantage plan, and you generally cannot have both.
04Receipts
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Plain-English answers from our glossary. Receipts included. Never advice.
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