How does a Medicare Part D plan determine drug costs and coverage?

• A. Based on a flat per-prescription price decided by CMS.
• B. Through its formulary with tiers, copays/coinsurance, and potential utilization controls like prior authorization.
• C. By the consumer's location alone.
• D. Only by the annual premium.

Answer: (B)

Medicare Part D costs and coverage come from the plan’s own design, not a single CMS price. Each Part D plan publishes a formulary, which is a list of covered drugs organized into tiers. The tier a drug sits in determines the member’s cost sharing—copays or coinsurance that vary by tier. Higher tiers generally mean higher out-of-pocket costs. Plans also use utilization controls, such as prior authorization, step therapy, and quantity limits, to manage which drugs are approved and in what amounts. These elements together—the formulary with its tiered cost sharing and any utilization management—set how much you’ll pay for a given drug and whether the drug will be covered at all. While premiums and where you live can affect plan choice and overall affordability, the actual drug costs and coverage come from the plan’s formulary design and its cost-sharing structure.