How to Compare Medicare Drug Plans During Open Enrollment (2027)

Here's the short version: don't pick a drug plan by its premium. Pick it by your drug list.

Every fall, from October 15 to December 7, you can change your Medicare drug coverage for the next year. Whatever you pick starts January 1. And if you do nothing, you usually just roll into next year with the same plan, changes and all.

That last part is where folks get caught. So let's walk through how I'd compare drug plans for 2027, step by step.

Think of your drug plan like a grocery store

Here's the mental model I use.

Your prescriptions are your grocery list. Every drug plan is a different store.

Some stores carry everything on your list. Some don't carry one or two items. Some put your items on the expensive shelf. Some want you to try the store brand first. And some give you a better price if you shop at their "preferred" location.

Now here's the kicker. Every January, every store rearranges the shelves.

So the store that was perfect this year might not be next year. You won't know unless you check.

Step 1: Make your real drug list

Before you look at a single plan, write down every prescription you take. Get it right:

• The exact drug name
• The strength (like 10 mg vs. 20 mg)
• How often you take it
• Whether you fill it every 30 or every 90 days

Grab your pill bottles or your pharmacy printout. A lot of folks I talk to forget the one they only fill a few times a year. That one counts too.

Wrong list, wrong answer.

Step 2: Read the letter your plan already sent you

If you're in a Medicare drug plan or a Medicare Advantage plan with drug coverage, your plan sends you an Annual Notice of Change each fall. It usually shows up in September.

Most people toss it. Don't.

That letter tells you what's changing for next year, like your costs, your coverage, and the drug list. If your plan isn't continuing in your area, you'll get a notice about that too.

Step 3: Check the formulary, not just the premium

The formulary is just the plan's list of covered drugs. It's the most important thing to check.

For each drug on your list, look for three things:

1. Is it covered? If it's not on the list, the plan generally doesn't have to pay for it.
2. What tier is it on? Plans sort drugs into tiers. Lower tiers usually cost you less. A drug can move tiers from one year to the next.
3. Are there rules attached? Watch for prior authorization (the plan has to approve it first), step therapy (you try a different drug first), and quantity limits (a cap on how much you can fill at once).

Here's why it matters. A low-premium plan can still cost you more over the year if your drugs sit on a high tier. The premium is the sticker. The yearly total is the price.

Step 4: Check your pharmacy

This one sneaks up on people.

Many drug plans have "preferred" pharmacies where your cost is lower, and "standard" pharmacies where it can be higher. Same drug, same plan, different pharmacy, different price.

So ask two questions:

• Is the pharmacy I use now in this plan's network?
• Is it preferred or standard?

If you're loyal to your hometown pharmacy here in Springfield, make sure the plan you pick likes it as much as you do.

Step 5: Compare the yearly total, not the monthly bill

Now put it all together. For each plan you're looking at, add up:

• The monthly premium for 12 months
• The deductible, if the plan has one
• What you'd pay for each drug, every fill, all year

That's your real number. That's the one to compare.

Doing this by hand for a bunch of plans is a lot of math. So we built a tool for it. Our Medicare plan finder lets you enter your ZIP code and your drugs, and it estimates what each plan in your county would cost you for the year, premium included. It's an estimate, so we always double-check the final pick with you before anything gets submitted.

Not sure how many plans are even available where you live? Start with the ZIP code plan checker.

Two newer rules worth knowing in 2027

There's a yearly cap on Part D drug costs. Medicare drug coverage now has an annual limit on what you pay out of pocket for covered drugs. Once you hit it, you don't pay more for covered drugs the rest of that year. If you take expensive medications, factor that in.

You can spread your drug costs out by month. It's called the Medicare Prescription Payment Plan. Instead of paying a big amount at the pharmacy counter, you get a monthly bill from your plan. If you're already using it and you stay in the same plan, it generally renews on its own. If you switch plans, you'll need to sign up again with the new plan.

When can I change my Medicare drug plan?

The main window is Open Enrollment: October 15 to December 7. Your new plan has to get your request by December 7, and coverage starts January 1.

If you're in a Medicare Advantage plan, there's also a second window from January 1 to March 31. During that time you can switch to another Medicare Advantage plan, or drop back to Original Medicare and pick up a separate drug plan.

Outside of those windows, you generally need a qualifying life event, like moving or losing other coverage, to make a change.

My advice? Don't wait until December 6. Do your homework in October or November while you have time to ask questions.

3 things I'd never do when comparing drug plans

1. Never pick a plan by premium alone. Cheap sticker, expensive year. Run the yearly total.
2. Never assume this year's plan is fine next year. The shelves get rearranged every January. Check.
3. Never skip drug coverage just because you're healthy. If you go without Medicare drug coverage or other creditable coverage for 63 days or more in a row after you're first eligible, you can owe a late enrollment penalty for as long as you have drug coverage.

Want a second set of eyes on your drug list?

That's what we do every day. Bring your drug list and your Annual Notice of Change, and we'll compare the plans with you, side by side.

Call us at (417) 633-7200, or stop by our Springfield office at 3616 S Campbell Ave.

Let's get you set up right for 2027.

— Matt

Frequently asked questions

What happens if I don't do anything during Open Enrollment?

In most cases, you stay in your current plan, and whatever changes the plan made for next year take effect January 1. If your plan is leaving your area, you'll get a notice and you'll need to pick new coverage.

How do I find out if my drugs are covered next year?

Check the plan's formulary for next year, not this year. Your Annual Notice of Change will flag changes. You can also enter your drug list in our plan finder, or call us and we'll check it with you.

Is the plan with the lowest premium the cheapest plan?

Not always. Your total yearly cost depends on the premium, the deductible, the tier your drugs sit on, and the pharmacy you use. That's why we compare the full year.

Do I need a separate drug plan if I have a Medicare Supplement?

Yes, if you want drug coverage. Medicare Supplement plans don't cover prescriptions. Most people with a supplement pair it with a standalone Part D plan.

Can I change drug plans more than once during Open Enrollment?

Yes. You can make changes as many times as you want between October 15 and December 7. The last one you make by December 7 is the one that counts.