Your Plan & Drug Costs
Based on the CMS standard Part D benefit design for 2026. Your actual plan may have a lower deductible or different tiers — check your Evidence of Coverage for exact numbers.
Month-by-Month Breakdown
| Month | Phase | Retail Cost | You Pay | Cumulative OOP | Plan Pays |
|---|
How the 2026 Medicare Part D Benefit Works
The Inflation Reduction Act eliminated the old "donut hole" coverage gap starting in 2025. The redesigned Part D benefit now has three phases, and this calculator walks your spending through all three:
1. Deductible
You pay 100% of drug costs until you've spent the annual deductible ($615 standard for 2026).
2. Initial Coverage
You pay 25% coinsurance; your plan pays the rest — until your total out-of-pocket spending hits $2,100.
3. Catastrophic
Once you've spent $2,100 out of pocket, you pay $0 for covered Part D drugs for the rest of the calendar year.
What Counts Toward the $2,100 Cap?
Your deductible payments and 25% coinsurance both count toward the $2,100 true out-of-pocket (TrOOP) threshold. Manufacturer discounts on brand-name drugs in the coverage phase also count toward TrOOP under current rules — this calculator assumes your own cash/coinsurance payments only, so if you take expensive brand-name drugs you may hit the cap faster than shown here.
Why This Matters More for Some Drugs
If your monthly drug costs are high — GLP-1 medications, specialty drugs, or several brand-name maintenance medications — you're likely to blow through the deductible and coinsurance phases in just a few months and spend most of the year paying $0. If your costs are low, you may stay in the 25% coinsurance phase the entire year and never reach the cap.
About This Estimator
This tool models the CMS standard Part D benefit design published for 2026 (deductible, coinsurance rate, and out-of-pocket threshold). Actual Part D plans vary — some have $0 deductibles, different drug tiers, or additional supplemental coverage. This is a planning estimate, not a guarantee of your actual costs. For your specific plan's numbers, check your plan's Evidence of Coverage or Medicare.gov's Plan Finder.
Also Compare Cash Prices
If you're not yet on Medicare, or want to compare cash vs. plan pricing, use our full drug price tool.
Compare Drug Prices →