Medicare Part D Drug Cost Estimator

Understanding Medicare Part D Coverage Phases

Medicare Part D drug coverage is organized into four phases that determine how much you pay at different points during the year. Understanding these phases is crucial for estimating your annual drug costs and choosing the right Part D plan.

Phase 1 — Deductible: In 2025, the maximum Part D deductible is $590. You pay full price for your drugs until you have spent this amount. Not all plans have a deductible, and some plans have a deductible that only applies to certain drug tiers. Once you have met the deductible, you enter the initial coverage phase.

Phase 2 — Initial Coverage: After meeting the deductible, you pay copays or coinsurance (typically 25%) for covered drugs. This phase continues until your total drug costs (what you and your plan have paid combined) reach a predetermined threshold. During this phase, generic drugs typically have the lowest copays while specialty medications have the highest.

Phase 3 — Coverage Gap: Previously known as the 'donut hole,' this phase now requires you to pay 25% of drug costs. The coverage gap continues until your true out-of-pocket spending reaches $8,000 in 2025. Once you hit this threshold, you enter catastrophic coverage.

Phase 4 — Catastrophic Coverage: Thanks to the Inflation Reduction Act, once your out-of-pocket drug costs reach $8,000 in 2025, you pay $0 for all covered drugs for the remainder of the year. This is a major improvement from previous years and provides significant financial relief for beneficiaries taking expensive medications.