The short answer
There is no universal best Medicare Part D plan. The plan that fits you is the one covering your exact drugs at your pharmacy for the lowest total 2027 cost, premium plus deductible plus copays. Under the 2027 standard benefit, no plan may set a deductible above $700, and out-of-pocket spending on covered drugs stops at $2,400. Compare on Medicare Plan Finder during October 15 to December 7.
- 2027 deductible limit: No Medicare drug plan may have a deductible above $700 in 2027, up from $615 in 2026, and some plans have none.
- 2027 out-of-pocket cap: CMS set the annual Part D out-of-pocket threshold at $2,400 for 2027, up from $2,100 in 2026.
- Star ratings: CMS rates standalone drug plan contracts on up to 12 quality measures, and the ratings appear on Medicare Plan Finder for Open Enrollment.
- Enrollment window: AEP runs October 15 to December 7 for coverage starting January 1, 2027.
Applies to people with Medicare who take prescription drugs and are choosing a standalone Part D plan or a Medicare Advantage plan with drug coverage for 2027; if you have employer, retiree, VA or Extra Help coverage, the comparison steps change.
Is there a best Medicare Part D plan for 2027?
No, and any page that names one without knowing your prescriptions is guessing. Part D is sold by private companies approved by Medicare, and each plan sets its own drug list, tiers and pharmacy pricing. All Part D plans generally must cover at least two drugs per drug category, but each plan chooses which Part D drugs it offers.
That is why two neighbors on the same street can get opposite answers. One takes three generics and pays almost nothing on a low-premium plan. The other takes a specialty drug and does better on a plan with a higher premium and better tier placement.
The useful question is not which plan is best overall. It is which plan produces the lowest total 2027 cost for your list of drugs at the pharmacy you actually use. Our Part D resource hub covers the mechanics behind that comparison.
What four factors decide which Part D plan fits you?
1. The formulary
The formulary is the plan’s list of covered drugs. If a specific drug is not on the list, a similar drug is usually available, but you should not assume that. Check each drug by name, strength and quantity.
2. The tier your drug sits on
A drug in a lower tier generally costs you less than a drug in a higher tier. Medicare’s own example shows Tier 1 holding most generics, Tier 2 preferred brand-name drugs and Tier 3 non-preferred brands. The same drug can land on different tiers in different plans.
3. The pharmacy
Plans negotiate different prices with different pharmacies, and many use preferred cost-sharing pharmacies where copays are lower. Mail order can price differently again. Your estimated yearly cost can move simply by changing which pharmacy you select.
4. Total annual cost, then star rating
Add premium, deductible and your drug copays for the full year. Only after that should a quality rating break a tie. CMS rates standalone drug plan contracts on up to 12 quality and performance measures, using cut points that assign one to five stars on each measure.
How do you use Medicare Plan Finder step by step?
Medicare Plan Finder on medicare.gov is the one tool that prices your specific drugs against every plan in your ZIP code. Star ratings appear on Plan Finder for Open Enrollment, so quality and cost sit on the same screen.
Run your 2027 comparison in about 20 minutes
- Write down every prescription with its exact strength, quantity and how often you refill it.
- Go to medicare.gov, open Plan Finder and enter your ZIP code and county.
- Enter each drug, then add the pharmacy you use, plus a mail-order option if you would use one.
- Sort by lowest estimated yearly cost, which combines premium and your drug costs, not premium alone.
- Open two or three plans side by side and check tier, prior authorization, step therapy and quantity limits on your most expensive drug.
- Confirm the star rating, then enroll or call us before December 7.
Do this with your Annual Notice of Change in hand. Our walkthrough on reading your 2027 ANOC in ten minutes shows which four lines to pull before you start.
How do the 2027 changes affect which plan fits you?
Two federal numbers reset every January and shape your math. No Medicare drug plan may have a deductible above $700 in 2027, compared with $615 in 2026, and some plans have no deductible at all. CMS finalized the 2027 annual out-of-pocket threshold at $2,400, up from $2,100 in 2026.
| Standard Part D figure | 2026 | 2027 |
|---|---|---|
| Maximum plan deductible | $615 | $700 |
| Annual out-of-pocket threshold | $2,100 | $2,400 |
| National base beneficiary premium | [VERIFY: 2026 figure on CMS fact sheet] | $41.33 |
CMS describes the national base beneficiary premium as the starting point for calculating a plan-specific basic premium, and set it at $41.33 for 2027. It is not the premium you pay. Plan premiums are set plan by plan, which is why we cover the drivers separately in why your 2027 Part D premium is going up.
A higher deductible changes early-year cash flow more than it changes your annual total, since deductible spending counts toward the cap. Details on what counts sit in our post on the $2,400 Part D cap in 2027, and the full picture is in Part D changes for 2027.
Why can your best plan change from one year to the next?
Three things move annually: your medications, the plan’s formulary and tiers, and the plan’s premium and cost sharing. Any one of them can flip the ranking. A plan that finished first for your list last December can finish fourth this December with no action from you.
Star ratings move too. The enrollment-weighted average overall rating for Medicare Advantage plans with drug coverage was 3.98 for 2026, after 3.95 for 2025, and individual contracts rise and fall as cut points are recalculated. Re-running the comparison each fall is the whole job.
One exception to the calendar is worth knowing. If you live in the service area of a plan with an overall quality rating of 5 stars, you may join it once between December 8 and November 30 of the plan year. You can only switch to a 5-star drug plan if one is available in your area.
What mistakes do people make comparing Part D plans?
Shopping on premium alone. A low premium with your drug on a non-preferred tier can cost more across twelve months than a higher premium with better placement.
Skipping the pharmacy step. Entering drugs but leaving the default pharmacy produces a number you will never actually pay.
Ignoring coverage rules. Prior authorization, step therapy and quantity limits decide whether a covered drug is easy or slow to fill. If none of the drugs on the list will work for your condition, you or your prescriber can ask for an exception, and a tiering exception can lower the amount charged for a drug on a non-preferred tier.
Assuming Part D covers everything. Part B generally covers drugs you would not give yourself, such as those administered in a doctor’s office, and Part D covers drugs Part B does not.
Waiting until December 5. Deadlines compress, hold times grow, and rushed comparisons produce regret in February. If you want help, our licensed agents work by phone and video, and you can reach us through our contact page or start at the Medicare hub.
Questions people ask
Do I have to switch Part D plans every year?
No. You can stay in your plan and it will usually renew automatically. The point of comparing is to confirm your 2027 drug list, pharmacy and total cost still work. Many people re-run Plan Finder and keep what they have.
What if my 2027 plan drops one of my drugs?
Your plan's drug list may not include a specific drug, but a similar drug is usually available. You or your prescriber can request an exception, which asks the plan to cover a drug that is not on its list or to waive a coverage rule.
Does a 5-star rating mean the plan will cost me less?
No. Star ratings measure plan quality and performance, not your drug prices. A highly rated plan can still put your medication on a higher tier. Check your estimated yearly cost first, then use the rating as a tiebreaker between plans with similar costs.
Can I change Part D plans outside October 15 to December 7?
Sometimes. If a plan with an overall 5-star quality rating serves your area, Medicare allows one switch into it between December 8 and November 30. Other special enrollment periods exist for moves, coverage loss and similar events.
Does my monthly premium count toward the $2,400 cap?
No. The 2027 annual out-of-pocket threshold of $2,400 reflects what you pay for covered drugs. Premiums are billed separately. Two people in the same plan can reach the cap in different months depending on which drugs they fill and when.
What happens if I go without drug coverage in 2027?
You may owe a late enrollment penalty of 1 percent of the national base beneficiary premium for each full uncovered month. CMS set the 2027 national base beneficiary premium at $41.33. The penalty is generally added to your premium for as long as you have Part D.
Sources
- Announcement of CY 2027 Medicare Advantage Capitation Rates and Part C and Part D Payment Policies, April 6, 2026
- How much does Medicare drug coverage cost?, Accessed September 23, 2026
- How do drug plans work?, Accessed September 23, 2026
- Special Enrollment Periods, Accessed September 23, 2026
- 2026 Star Ratings Fact Sheet, Accessed September 23, 2026
- Medicare Part D 2027 National Average Monthly Bid Amount Information, July 28, 2026
Want a second set of eyes on your 2027 drug list?
We run Medicare Plan Finder with you by phone or video, using your actual medications, doses and pharmacy, and we explain what changes for 2027 before December 7. We are licensed in more than 40 states, not California, and there is no cost to talk.
Request a Part D reviewCall or text (773) 657-9140Smart Insurance Agents LLC is an independent, licensed insurance agency and is not connected 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, 1-800-MEDICARE, or your local State Health Insurance Assistance Program for information on all of your options. Content is for general information and is not a guarantee of coverage or rates; figures are subject to change by CMS and carriers.