How to pick a Part D plan that actually covers your prescriptions — not just the cheapest one.
Choosing a Part D plan based on premium alone is one of the most common and expensive mistakes Medicare beneficiaries make.
What actually matters:
1. Formulary. Does the plan cover your specific drugs? Every plan has a formulary — a list of covered drugs organized into tiers. Whether your drugs are on the formulary matters far more than the monthly premium.
2. Drug Tier. Which tier are your drugs on? Tier 1 (generics) might cost $0–5, while Tier 4–5 drugs can cost hundreds. The same drug can be on different tiers in different plans.
3. Pharmacy Network. Is your preferred pharmacy in-network? Using an out-of-network pharmacy can dramatically increase your costs.
4. Total Annual Cost. Add up the premium plus your estimated drug costs for the year. The plan with the lowest premium often isn't the lowest total cost.
How to compare the right way: Enter your exact medications and preferred pharmacy into a plan-comparison tool (like the one on this site, or Medicare.gov's Plan Finder). It will calculate estimated annual costs for every plan in your area.
New for 2026: The out-of-pocket cap for Part D is $2,000. Once you hit $2,000 in drug costs, you pay $0 for the rest of the year — a huge change that can save people with expensive prescriptions thousands.
A licensed advisor can walk you through your options in plain English — for free, with no obligation.
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SeniorPlanFinder.com is operated by Direct to Consumer Insurance Services, LLC and is not affiliated with or endorsed by the U.S. Government or the federal Medicare program. We do not offer every plan available in your area. Please contact Medicare.gov or 1-800-MEDICARE to get information on all your options.