To compare Part D plans, enter your exact drugs and pharmacy into Medicare's Plan Finder at Medicare.gov/plan-compare and look at each plan's total yearly cost. Do it between October 15 and December 7. Any change you make starts January 1, and a plan with a low premium can still cost more once you add the deductible and your copays.
When can I change my Part D plan?
Medicare's Open Enrollment runs from October 15 to December 7 each year. During that time, Medicare.gov says you can join, switch, or drop a Medicare drug plan or a Medicare Advantage Plan, or switch to Original Medicare. The new coverage starts January 1.
If you're in a Medicare Advantage Plan, there's a second chance from January 1 to March 31. If you have Original Medicare with a separate drug plan, that later window doesn't let you switch from one drug plan to another. If you have a stand-alone Part D plan, fall is your main chance to switch. The Medicare Advantage Open Enrollment Period explains the spring window.
What will Part D cost in 2027?
Medicare.gov has published the 2027 limits:
| 2026 | 2027 | |
|---|---|---|
| Highest deductible a plan can have | $615 | $700 |
| Yearly out-of-pocket cap on covered drugs | $2,100 | $2,400 |
After the deductible, Medicare.gov says you pay 25% coinsurance for covered drugs until your out-of-pocket spending reaches the cap. After that, you pay nothing for covered Part D drugs for the rest of the year. Some plans have no deductible, and your plan's actual copays may differ.
Premiums vary by plan and where you live, so you'll see them in Plan Finder. The Part D out-of-pocket cap and Prescription Payment Plan explains how the cap works.
What should I gather before I compare?
Line up your pill bottles and write down each drug's exact name, strength, and how often you take it. Note your pharmacy, and whether you'd try mail order. Your Part D Explanation of Benefits shows what you paid this year. Your plan's Annual Notice of Change lists what changes in January. See your Annual Notice of Change.
How do I use Plan Finder to compare?
- Go to Medicare.gov/plan-compare. You can log in or continue without logging in.
- Pick drug plans (or Medicare Advantage plans with drug coverage).
- Enter your drugs and doses.
- Pick your pharmacy, and a second one if you'd like to compare.
- Sort the results so the lowest total of drug costs and premiums is at the top.
Then open the top few plans and check:
- Is every drug on the plan's list? Look for any drug marked as not covered.
- What tier is each drug on? Higher tiers usually cost more.
- Does a drug need prior authorization, or have a quantity limit or step therapy? That means extra paperwork.
- Is your pharmacy "preferred"? Prices can differ between pharmacies in the same plan.
- What's the deductible? A plan with a $700 deductible can cost a lot in January and February, even with a low premium.
How can a low-premium plan cost more?
Say a plan has a small premium but leaves one of your drugs off its list, or puts it on a high tier. Over a year, that can cost more than a plan with a higher premium. Plan Finder's yearly estimate adds premiums and expected drug costs together, so use that number to compare.
If you take only a few low-cost drugs, a low-premium plan may still fit. Medicare.gov suggests getting a low-premium drug plan even if you don't take many drugs now, so you can avoid the late enrollment penalty. See Medicare late enrollment penalties.