Part D Cost Components
Medicare Part D has four main cost components:
| Cost Type | 2026 Amount | Notes |
|---|---|---|
| Monthly Premium | ~$0 – $100+ | Average ~$46/month; varies by plan |
| Annual Deductible | Up to $615 | Some plans have $0 deductible |
| Copays/Coinsurance | Varies by tier | $0–$15 for generics; 25–33% for specialty |
| Out-of-Pocket Cap | $2,000 | After $2,000 OOP, you pay $0 |
IRMAA: Part D Income Surcharges
Higher-income beneficiaries pay an additional amount (IRMAA) on top of their plan premium. In 2026:
| Individual Income | Monthly IRMAA Surcharge |
|---|---|
| $109,000 or less | $0 |
| > $109,000 and < $137,000 | $14.50 |
| > $137,000 and < $171,000 | $37.50 |
| > $171,000 and < $205,000 | $60.40 |
| > $205,000 and < $500,000 | $83.30 |
| > $500,000 | $91.00 |
IRMAA is paid directly to Medicare, not to your Part D plan. It's added to your Social Security benefit deduction or billed directly if you don't receive Social Security.
Estimating Your Total Annual Part D Cost
To estimate your total annual Part D cost, add together:
- 12 × monthly premium
- Annual deductible (if applicable)
- Estimated copays for your medications based on their tiers
- IRMAA surcharge (if applicable)
Medicare.gov Plan Finder calculates your estimated total annual cost automatically when you enter your medications. This is the most accurate way to compare plans.