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Coinsurance

The percentage of costs you share with Medicare after meeting your deductible.
Reviewed by Aaron Sims, Licensed Life & Health Agent since 2012

Medicare Term

Definition

The percentage of costs you share with Medicare after meeting your deductible.

Coinsurance is your share of the cost of a Medicare-covered service, calculated as a percentage. For most Part B services, you pay 20% coinsurance after meeting the annual deductible. Coinsurance amounts vary depending on the type of service and whether you have Original Medicare or a Medicare Advantage plan.

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