Blog / Part D

How do I compare Medicare Part D plans?

A step by step method that takes about thirty minutes and routinely saves people hundreds a year.

Updated August 17, 2026 · 2 min read

Comparing drug plans is the highest return half hour in Medicare, and it is genuinely simple if you do it in the right order. The mistake is starting with premiums.

Step 1: build your drug list

Write down every prescription with the exact dosage, the quantity per fill, and how often you refill. Note whether you take the brand or generic.

Include anything seasonal or occasional. A medication you fill twice a year still counts.

Step 2: run it through the Plan Finder

1. Go to Medicare.gov and enter your ZIP code.
2. Enter every drug with its dose.
3. Add your usual pharmacy, and add a second pharmacy and a mail order option to compare.
4. Sort results by total estimated annual cost.

Step 3: check the top three for restrictions

The cheapest total is not always the best plan. Look at each of the top few for:

• Prior authorization on any of your drugs
• Step therapy, which forces you to try something cheaper first
• Quantity limits below what you are prescribed
• Whether your pharmacy is preferred or standard

A plan that saves you money but requires step therapy on a medication you are stable on is not a saving.

Step 4: sanity check the plan itself

• Star rating, as a rough measure of service and quality
• Whether the carrier is one you can actually reach on the phone
• Whether the plan has been stable year to year or churns its formulary

Step 5: decide, then diarize

Enroll during your window, then put a note in your calendar for the first week of October next year to do this again. Formularies and tiers change annually, and the best plan this year is frequently not the best plan next year.

The mistakes worth avoiding

• Choosing on premium alone. The most common and most expensive error.
• Assuming your plan is still the best because it was last year.
• Not entering exact doses, which can put a drug on a different tier.
• Forgetting to check the pharmacy. Preferred versus standard can be a large difference.
• Ignoring a step therapy flag because it looks like fine print.

If you would rather not do it alone

We run this comparison as a matter of course, at no cost, across every plan available at your address. Bring your pill bottles or a printed list from your pharmacy and it takes about half an hour.

See checking a formulary and what Part D costs.