How Medicare Part D Covers Insulin

Medicare Part D covers insulin, but not all insulins the same way. Your coverage depends on which Part D plan you chose, because each plan maintains its own formulary — a list of covered drugs and their cost-sharing rules. Some plans cover all insulin types; others require you to try a cheaper insulin first before they will pay for a brand-name one. The insulin itself is the same medication whether you buy it at the pharmacy or through a mail-order service, but your out-of-pocket cost can swing by hundreds of dollars depending on your plan's formulary and which pharmacy you use.

Part D plans must cover at least two insulins in each category — rapid-acting, short-acting, intermediate-acting, and long-acting — so you will have options. However, "covered" does not mean affordable. A plan might cover Humalog (rapid-acting insulin lispro) with a $50 copay but cover Novolog (rapid-acting insulin aspart) with a $5 copay. If your doctor prescribed Humalog, you either pay the higher copay, ask your doctor to switch you, or request an exception from your plan.

Key Takeaways

  • Every Part D plan must cover at least two insulins in each category (rapid-acting, short-acting, intermediate-acting, long-acting), but the specific insulins and their copays vary by plan.
  • Your plan's formulary lists which insulins are covered and at what cost tier; you can view it on your plan's website or call the plan to ask about a specific insulin.
  • If your doctor prescribed an insulin that is not on your plan's formulary or costs too much, you can request a coverage exception, which usually takes three to five business days.
  • Insulin prices at the pharmacy counter vary widely by location and pharmacy chain, so comparing prices before you fill the prescription can save you money even within the same plan.
  • If your insulin cost exceeds $35 per month, you pay only $35 for the rest of the year once you reach that threshold — a protection that applies to all Medicare beneficiaries on Part D.

Finding Your Insulin on Your Plan's Formulary

Your Part D plan publishes its formulary online, usually as a searchable PDF or database on the plan's website. Log in to your plan's member portal, or call the customer service number on your insurance card and ask them to tell you the copay or coinsurance for the specific insulin your doctor prescribed. Have the insulin name and strength ready — for example, "Lantus 100 units per milliliter" — because insulin names alone are not specific enough.

If you do not yet have a Part D plan and you know you take insulin, you can compare formularies before you enroll. Visit Medicare.gov, use the Plan Finder tool, enter your insulin names, and the tool will show you which plans cover them and at what cost. This step takes 10 to 15 minutes and can prevent you from choosing a plan that makes your insulin unaffordable.

What Happens If Your Insulin Is Not Covered

If your insulin is not on your plan's formulary at all, or if the copay is too high, you have three options: switch to a covered insulin, request a coverage exception, or pay out of pocket and ask for a receipt to count toward your deductible.

A coverage exception (also called a formulary exception) is a written request to your plan asking them to cover a drug that is not on the formulary, or to move it to a lower cost tier. Your doctor must submit the request or sign off on it. The plan has three to five business days to respond. Plans often approve exceptions when the patient has tried the covered alternatives and they did not work, or when the prescribed insulin is medically necessary for a specific reason. Call your plan's customer service line and ask for the exception request form — they can mail it, email it, or fax it to your doctor's office.

If you cannot wait for an exception decision, you can fill the prescription at your own cost. Keep the receipt. Once you reach your deductible for the year, the out-of-pocket amount you paid counts toward it, and your plan will begin sharing costs with you.

The $35 Monthly Insulin Copay Cap

Starting in 2024, Medicare Part D limits your copay for insulin to $35 per month, regardless of the insulin type or dose. This cap applies only to insulin you inject or inhale — not to oral diabetes medications. Once you have paid $35 in copays for insulin in a calendar month, your plan covers the rest of your insulin at no additional cost for that month.

This cap does not explore to your deductible. If your plan has a deductible and you have not met it yet, you still pay the full price of insulin until the deductible is satisfied. After that, the $35 cap takes effect. The cap also does not lower the price at the pharmacy if you are uninsured or on a plan without Part D coverage.

Comparing Insulin Prices at Different Pharmacies

The same insulin at the same dose can cost different amounts at different pharmacies, even within the same insurance plan. A vial of Lantus might cost $45 at one pharmacy and $60 at another, both in your network. Before you fill your prescription, call three pharmacies — your usual one, a large chain, and a mail-order service if your plan offers one — and ask the price for your specific insulin, strength, and quantity.

Some pharmacies offer discount programs that stack with your insurance copay. GoodRx, SingleCare, and similar discount cards sometimes offer a lower price than your copay, though this is rare with insulin. Ask the pharmacy if they will price-match or if they have a loyalty program. Mail-order pharmacies often offer a 90-day supply at a lower copay than a 30-day supply at a retail pharmacy, so compare the per-month cost, not just the total price.

Switching Plans If Your Insulin Costs Too Much

If you enrolled in a Part D plan and later discovered that your insulin copay is unaffordable, you can switch plans during the annual open enrollment period (October 15 to December 7 each year) or if you experience a may have access to life event. You do not have to wait until next year.

A may have access to event includes losing your current coverage, moving to a new state, or having a significant change in your income. If you believe your insulin costs are a hardship, contact your plan and ask whether they consider that grounds for a special enrollment period. Some plans will allow you to switch if you can document that your copay exceeds a certain percentage of your income.

Before you switch, use the Plan Finder tool again to confirm that the new plan covers your insulin at a lower copay. Switching plans is free, but it takes effect on the first of the following month, so plan ahead if you are running low on insulin.

Insulin Samples and Patient information Programs

If you cannot afford your copay while waiting for a coverage exception or plan change, ask your doctor for sample vials or pens. Many insulin manufacturers provide free samples to patients, and a month's supply of samples can bridge the gap while you sort out your coverage.

Insulin manufacturers also run patient information programs that provide free or low-cost insulin to people who meet income limits. These programs are separate from Medicare and do not count as insurance. Eli Lilly, Novo Nordisk, and Sanofi all offer programs; you can find them by searching the manufacturer's name plus "patient information" or by calling your doctor's office, which often has applications on hand.

Frequently Asked Questions

Does Medicare Part D cover insulin pens and syringes?

Part D covers the insulin itself, but not the devices you use to inject it. Syringes, needles, and insulin pens are covered under Medicare Part B as durable medical equipment if your doctor writes a prescription. You pay 20 percent coinsurance after you meet your Part B deductible. Some Part D plans do cover insulin pen devices; call your plan to ask.

What if I take two different types of insulin?

The $35 monthly copay cap applies to all insulin combined, not per insulin. If you take a long-acting insulin and a rapid-acting insulin, your total copay for both cannot exceed $35 per month once you reach that threshold. Each insulin counts separately toward your deductible.

Can I use a GoodRx coupon instead of my Part D insurance?

Yes, you can choose to use a discount card instead of your insurance, but you cannot use both at the same time. Compare the GoodRx price to your copay before you fill the prescription. If GoodRx is cheaper, you can use it, but that amount will not count toward your Part D deductible or out-of-pocket maximum.

What if my doctor prescribed a brand-name insulin but my plan covers only the generic version?

Most insulins do not have generic equivalents — they are all brand-name drugs. However, some plans may prefer one brand over another and charge a higher copay for the non-preferred one. Ask your doctor if a preferred insulin would work for you, or request a coverage exception if the preferred option did not work in the past.

Do I have to use mail order for my insulin, or can I pick it up at a pharmacy?

You can use either. Some plans offer a lower copay for a 90-day mail-order supply than for a 30-day retail supply, but you are not required to use mail order. Check your plan's copay structure for both options and choose whichever is cheaper and more convenient for you.