How to Use Medicare Plan Finder to Check Your Drug Costs
Published October 31, 2026 路 6 min read 路 Figures last verified October 31, 2026
Reviewed by D.P., PharmD.
- Medicare Plan Finder, at medicare.gov/plan-compare, is Medicare's own tool for comparing plans in your ZIP code. It estimates total yearly costs for your drugs at your pharmacy, not just the monthly premium.
- Enter every prescription with its dose and how often you fill it, and enter the pharmacy you actually use. A missing drug, a wrong dose, or a different pharmacy can change the result.
- Sort and compare by total estimated yearly cost. Then check the details behind that number: whether each drug is covered, what tier it sits on, and whether it needs prior authorization, step therapy, or has a quantity limit.
- Plan Finder does not replace your plan's own documents. Your Annual Notice of Change, sent each fall, lists what actually changes next year.
- Annual Enrollment Period (AEP): October 15 to December 7. You can join, switch, or drop Medicare Advantage and Part D plans. Changes take effect January 1.
- Medicare Advantage Open Enrollment: January 1 to March 31. Already in a Medicare Advantage plan? You can switch to a different Advantage plan or back to Original Medicare once.
- General Enrollment Period: January 1 to March 31. Missed your initial window for Parts A and B? You can still sign up here; coverage starts the month after you sign up.
The monthly premium is the number most people see first, and it is the number that misleads most often. A plan with a low premium can still cost more over a year if your drugs sit on a high tier, if your pharmacy is not preferred for that plan, or if a drug needs extra paperwork first. A higher premium plan can cost less in total if it covers your drugs at lower copays. Plan Finder shows that full-year picture, for your drugs, at your pharmacy, before you enroll.
Plan Finder is run by Medicare, not by a plan or a discount card company. It compares standalone Part D plans and Medicare Advantage plans with drug coverage, in your area, using the drug list you enter. It does not recommend a plan, and it does not advise starting, stopping, or switching any medication. Those decisions belong to you, your doctor, and your pharmacist.
Before you open Plan Finder: gather your list
Plan Finder is only as accurate as the list you type in. Gather four things first.
First, every prescription, with drug name, dose, and how often you fill it. A 30 day supply and a 90 day supply are not the same entry, and a 10 mg tablet and a 20 mg tablet are not the same entry. If you are unsure, check the bottle or ask your pharmacy. Do not guess.
Second, your pharmacy, local, mail order, or both. Plans often charge different amounts at preferred, standard, and mail order pharmacies, so the pharmacy you enter matters as much as the drug list.
Third, your ZIP code. Plans, prices, and pharmacies are local.
Fourth, your plan's Annual Notice of Change, if you already have a plan. Sent each fall, it lists what changes for the next year: premium, deductible, drug tiers, and pharmacy rules.
Your pharmacy can print your current medication list, with names, strengths, and frequencies, for you to work from. That printout is the modern version of an older tip about a Drug List ID code. That code system ended in 2019, and no code is issued today. A printed list, plus a free Medicare.gov account that can save your list year to year, is how the same job gets done now. Never share your Medicare.gov password with anyone offering to keep your list for you.
The walkthrough, step by step
Step 1: Go to the official tool. Type medicare.gov/plan-compare into your browser address bar, rather than clicking a search ad, which can point to lookalike sites during open enrollment.
Step 2: Enter your ZIP code and choose a plan type. Plan Finder first asks where you live, then whether to compare standalone Part D plans, Medicare Advantage plans, or both. Match that choice to the coverage you have now.
Step 3: Enter your drugs, one by one. Search each drug by name, then select dose, quantity for a typical fill, and how often you fill it. Add every prescription, even one you fill only a few times a year. A drug left out is a drug cost left out of the total. In guest mode, you type each drug by hand and nothing is saved. With a free Medicare.gov account, your list can be saved year to year, and the tool can prefill drugs from your Medicare claims for the last 12 months, which you can check and edit.
Step 4: Enter your pharmacies. Add the pharmacy or pharmacies you actually use, including mail order. Plan Finder prices each plan using those pharmacies, so rerun the comparison if you change pharmacies.
Step 5: Sort by total estimated yearly cost. Results list plans by estimated total yearly cost: premium, deductible, and estimated drug costs for your list at your pharmacies. That total is the number to compare first, not the premium column alone.
Step 6: Open the plan details. Click into a plan to see the breakdown: monthly premium, annual deductible, drug costs by month, and coverage rules. Confirm each drug is covered, note its tier, and note any prior authorization, step therapy, or quantity limit flag. Those flags do not mean a drug is unavailable, but they do mean extra steps or limits may apply.
How to read the result without fooling yourself
Plan Finder's total is an estimate, not a bill. It is built from your drug list, your pharmacies, and the plan's published prices and rules for the coming year. It does not know about a later drug change, pharmacy change, or plan change. Rerun it if your list changes.
Three checks catch most errors. First, every drug, with the right dose and fill frequency. Second, the pharmacy column: preferred, standard, and mail order prices can differ, and a plan cheapest at one pharmacy may not be cheapest at yours. Third, the deductible and cap in context. Under the standard Part D benefit, the deductible is at most $700 in 2027, and covered drug costs are capped at $2,400 in 2027, after which covered drugs cost $0 for the rest of the year. Many plans charge less, so your plan's own documents set the actual numbers.
Also check what Plan Finder does not show. It does not rank plans by customer service, by how easy prior authorization is in practice, or by whether your doctor is in a Medicare Advantage network.
What to do with the result
Once you have a short list, compare the plan documents, not just the Plan Finder summary. Read the Annual Notice of Change for your current plan, and the new plan's summary of benefits, for the drugs and pharmacies that matter most. If a result surprises you, or a coverage flag is unclear, get free, unbiased help before you enroll. Your state's State Health Insurance Assistance Program, known as SHIP, offers free one-on-one Medicare counseling, and you can also call 1-800-MEDICARE. SHIP counselors do not sell plans.
If you decide to change plans, enroll by December 7, and the change takes effect January 1. If you do nothing, your current plan usually renews, with whatever changes it made for the next year. That is why the fall check matters even when you are happy with your current plan.
Finally, keep your list. Save it in your Medicare.gov account if you have one, or keep the pharmacy printout with your plan papers. Next fall, update only what changed: new drugs, stopped drugs, a new dose, or a new pharmacy. That updated list, run through Plan Finder again, is the whole routine.
This guide explains how Medicare Plan Finder works and how to compare drug costs across plans. It doesn't advise which coverage to choose, doesn't recommend any plan, and doesn't advise starting, stopping, or switching any medication. Those decisions belong to you, your doctor, and your pharmacist. For personal guidance, use Medicare Plan Compare or contact your local SHIP program. Full disclaimer.
Sources
- Medicare.gov, Medicare Plan Compare (official plan and drug-cost comparison tool, ZIP code, drug list, pharmacy, and total estimated yearly cost)
- Centers for Medicare & Medicaid Services, Announcement of Calendar Year (CY) 2027 Medicare Advantage (MA) Capitation Rates and Part C and Part D Payment Policies, April 6, 2026, Attachment V, Table V-2 (2027 standard deductible $700, 2027 out-of-pocket threshold $2,400)
- Centers for Medicare & Medicaid Services, guide "Adding Drugs & Pharmacies When Shopping for Plans," product 12075-P (Medicare.gov account saves drug list and pharmacies year to year, and can prefill drugs from Medicare claims for the last 12 months; guest mode requires typing each drug by hand, nothing saved)
- Medicare Rights Center, October 2019 (Drug List ID ended with the 2019 Plan Compare redesign: old IDs stopped working October 1, 2019, and the old-list lookup page closed December 7, 2019)
- State Health Insurance Assistance Program directory, shiphelp.org (free, unbiased one-on-one Medicare counseling in every state)