Medicare Part D is Prescription Drug Coverage

Medicare Part D helps cover the cost of prescription drugs. Part D plans are run by Medicare-approved private insurance companies.

Part D plans can be sold as standalone drug plans and paired with Original Medicare or Medigap. Meanwhile, many Part C plans include Part D coverage.

Part D plans have a premium, although you may qualify for “Extra Help” based on income to lower costs.

In terms of out-of-pocket costs, Part D plans each has a list of covered drugs called a “formulary.” Most plans then place certain drugs in levels called “tiers” and each tier has different costs in different cost-sharing phases. For example, a drug in a lower tier will have a lower cost than in a higher tier, and the cost-sharing of both drugs may be different in the initial coverage phase than they are in the coverage gap phase.

Citation: What Medicare Part D drug plans cover. CMS.Gov.

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Thomas DeMichele

Thomas DeMichele has worked in the online health insurance information space for over a decade. His works include, which has been used by nearly 40 million Americans since 2012 to learn about healthcare and health insurance.

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