Same pill, same plan, different counter: preferred pharmacy math

Thanks for having me. And yeah, Ian Schaeffer's piece really is one of those articles where once you see the rule, you cannot unsee it. He actually opens with a caller who was told the numbers at the pharmacy counter were two and three times what she was seeing on her computer. And the instinct is to assume someone made a mistake. The register, the insurance, something. But it was not a mistake.

Which is such a relatable way to put it, because this stuff is genuinely confusing. The reason it's confusing is that Medicare allows something called differential cost-sharing for preferred pharmacies. That's the regulatory term Ian Schaeffer cites, from 42 CFR 423.120(a)(9). What it means in practice is that your plan has a preferred network inside its network. A standard pharmacy is still in-network. Your drugs are still covered. You are just paying more there.

Correct, and that's worth separating out. There are actually three tiers of pharmacy here. You have the preferred in-network pharmacies, the standard in-network pharmacies, and then outside the network entirely. If you go out of network, Medicare's own language is that you'll probably have to pay full cost for the drugs. You can save your receipt and ask the plan for a partial refund, but you won't get back the out-of-network share. So that's the floor you really don't want to fall through.

Ian Schaeffer does the arithmetic in the article and it is clarifying. He uses made-up copays just to show the shape of the thing, so these are not real plan numbers, but the structure is real. Take three prescriptions: a Tier 1 generic for blood pressure, a Tier 2 generic for cholesterol, and a Tier 3 brand drug. At the preferred pharmacy the total comes to forty-seven dollars a month. At the standard pharmacy it comes to seventy-seven dollars a month. That's thirty dollars a month, three hundred sixty dollars a year, for the same three bottles, under the same plan.

And here's the part that surprised me when I read it. Look at where the gap actually lives in that example. The brand drug barely moves between the two counters. It goes from forty-two dollars to forty-seven. The spread on the generics is where the difference lives. The blood pressure generic goes from zero at the preferred pharmacy to ten dollars at the standard one. The cholesterol generic goes from five to twenty. People assume the cheap drugs cost nothing anywhere. But that's where the gap is widest.

It's counterintuitive. And it's worth pointing out that Ian Schaeffer is an engineer. He says so up front. He's not an advisor, and he didn't take this on faith when the caller reported it. He went and found the rule, then did the arithmetic. That's the whole structure of the piece, and it's why I find it persuasive.

So the Annual Notice of Change, the letter your plan sends you every fall, is where you'd start. Ian Schaeffer points to a specific section: Section 1.4 of the government template that every plan's notice follows. The language in there is pretty direct. It says the amounts you pay for your prescription drugs can depend on which pharmacy you use. And your specific copay tables are in Section 1.7. So if you've gotten that letter and set it aside, that's actually where you'd go.

It's pretty much been set aside. Which is why getting someone to run the numbers with you matters so much, and we'll get there. But first, let's talk about the pharmacy piece, because that's really a whole separate conversation.

It's essentially a fourth type of counter in this framework. Medicare allows plans to offer a program where you get up to a three-month supply of a covered drug sent directly to your home. For a stable daily medication, it's often the lowest copay on the list. That ninety-day supply can make real sense.

Two reasons from the rules themselves, as Ian Schaeffer lays them out. The first one is about access versus price. You are entitled to a ninety-day supply at a retail pharmacy. The plan cannot take that away from you. But the regulation specifically says a plan may require you to pay higher cost-sharing at a retail pharmacy compared with mail order. So you can get ninety days at your local pharmacy. You just might not get the mail-order price there.

Exactly the distinction. And the second reason is more practical. Mail order is a bad fit for a drug whose dose is still being adjusted. If your doctor is titrating something, you do not want a ninety-day box of the wrong dose sitting on your doorstep. And Ian Schaeffer also flags it as a logistics problem for anyone who splits the year between two addresses, which is a lot of our Arizona listeners. He mentions the article will pick that up in a piece specifically about snowbirds. A ninety-day box shipped to the wrong house in November is not a savings, as he puts it.

Exactly. So mail order is a tool, not a default. You want it working for you, not against you.

It is buried in the regulation and he says almost nobody knows it. A plan cannot prohibit a pharmacy from telling you that the cash price for a medication is lower than what you'd pay using your Part D plan. The plan cannot penalize the pharmacy for telling you either. So you can walk up to the counter and just ask: is the cash price lower than my copay? And they are allowed to tell you yes.

Because most people don't know they can. That's the whole thing. And for a lot of drugs, especially common generics, the cash price can be surprisingly low. So it is genuinely worth asking.

He is, and this is where the engineer in him shows up. The 2026 out-of-pocket cap on covered Part D drugs is two thousand one hundred dollars. But that cap only counts what you spend through the plan. If you pay cash and the plan never sees the claim, it generally cannot count that spending toward your cap. So here's the real trade. If you're someone on a handful of cheap generics who will never get close to that cap anyway, paying cash for a couple of them is probably fine. But if you have one expensive brand-name drug and you're on track to hit the cap by June, paying cash for your cheap generics in January might actually slow down the clock on the protection that covers you in July.

That is the real arithmetic. And Ian Schaeffer is explicit: this is the kind of question worth an hour with an advisor rather than a guess at the counter. I'd add, when you're at the pharmacy and you're trying to figure out whether to pay cash or run it through the plan, that's exactly the kind of question I'd write down and bring to one of our advisors. The specific mechanics of how the plan tracks the claim matter there, and getting that wrong has real consequences.

Three of them in the article. The first is insulin. Regardless of counter, regardless of preferred or standard, a one-month supply of each Part B- and Part D-covered insulin product is capped at thirty-five dollars. No deductible either. That's a fixed protection.

The second is vaccines. You pay nothing out of pocket for Part D adult vaccines recommended by the Advisory Committee on Immunization Practices. Ian Schaeffer specifically calls out the shingles shot. Zero out of pocket. And the third is the Medicare Prescription Payment Plan, which is a spreading mechanism for people whose drug bills bunch up early in the year. Instead of paying a large amount in January or February, you can spread those costs across the calendar year.

It does, but Medicare's own language is direct: it doesn't lower your drug costs or reduce what you owe overall. It changes when you pay, not how much. So it's a cash-flow tool. For someone on a fixed income who would otherwise have a brutal February, that's genuinely helpful. But it is not a discount.

Which is why Ian Schaeffer includes the caveat directly from Medicare rather than glossing over it.

This one matters a lot outside the metro area. The rules require that at least ninety percent of a plan's urban members live within two miles of a network retail pharmacy. For suburban members it's ninety percent within five miles. But for rural areas it drops: seventy percent within fifteen miles. Seventy, not ninety. Ian Schaeffer mentions Kingman and Pahrump as examples. If you're in that kind of area, the plan is structurally allowed to be thinner where you are. The nearest pharmacy might not be a preferred pharmacy. It might not even be in-network.

Right. And it's not a bug, it's a rule. Which means you need to know it upfront, not after you're already paying the higher price.

Medicare's plan finder is the tool. You can enter your own pharmacies, your actual drugs, and see what each one costs at each pharmacy. Ian Schaeffer notes that next year's plans are available in the tool from October 1 each year. The tool lets you manage a list of preferred pharmacies and any prescription drugs, and it gives you an estimate of out-of-pocket costs. The key is to enter the pharmacy you actually use, not the one that's technically closest to your house. Then put in the other one. Run both. That difference, the three hundred sixty dollars in the example, becomes visible before you sign anything.

Ian Schaeffer describes what a Certified Medicare Planner does in a way that I thought was really useful. The first question they ask is not which plan do you want. It's which pharmacy do you use. Because the plan that is cheapest at one counter is not the cheapest at another. They run your specific prescriptions through the plan finder at your pharmacy and at the preferred one, and they give you the actual number. They know when mail order is the right call and when it becomes, as he puts it, a box on the wrong porch.

They know it and they re-check it every single fall, which is the part people don't always realize. Preferred networks can change from one plan year to the next. A pharmacy that was preferred last year might not be preferred this year. That's exactly why Section 1.4 exists in that document we were just talking about -- that fall letter from your plan. They're required to spell it out for you, but only if you actually read it.

And that's a completely reasonable thing to need help with. One of the things I appreciate about Ian Schaeffer's approach in this piece is he's not making people feel foolish for not knowing this. Like we mentioned, it wasn't obvious even to him. He had to dig into it himself, do the arithmetic, confirm it was actually real. Most people don't have time to do that, and they shouldn't have to guess.

And those workshops are a good place to bring your plan letter and your prescription list and actually work through the numbers for your situation. That's the kind of thing where seeing your specific drugs and your specific pharmacy in the tool makes everything concrete.

That's the summary I'd want someone to tape to their refrigerator before open enrollment. And if any part of it made you think of a specific situation you're in, that's the sign to make a call.