The $35 Insulin Cap: What Medicare Part D Covers for Diabetes Medications

The Inflation Reduction Act of 2022 created one of the most significant prescription drug benefits for Medicare beneficiaries in recent memory: a $35 monthly cap on cost-sharing for covered insulin products under Part D. For the roughly 3.3 million Medicare beneficiaries who use insulin, this represents a meaningful and often immediate reduction in medication costs. But the cap comes with specific rules about which insulins qualify and how it interacts with the Part D deductible.

Bryce's Take

The $35 insulin cap is one of those benefits I make sure every diabetic client on Medicare knows about. I still see clients who switched to OTC insulin at Walmart to save money and do not realize their Part D would cover their prescription insulin for $35. Always check your plan's formulary before you go out of pocket on any medication.

What the $35 cap covers

Starting January 1, 2023, every Medicare Part D plan, including the drug coverage bundled into Medicare Advantage plans, must cap beneficiary cost-sharing for covered insulin at $35 per month per insulin product. The cap applies regardless of which cost-sharing tier the insulin falls on in the plan formulary. An insulin product that would normally be Tier 3 or Tier 4 under standard formulary rules is still capped at $35 for the month. The cap applies during all phases of Part D coverage, including any period in the deductible phase.

The deductible exemption

Part D plans typically charge beneficiaries full price for drugs during the annual deductible phase, which can run up to $590 in 2025. Insulin is explicitly exempt from this deductible for plans that cover insulin. Your cost for covered insulin is $35 or less per month even before you have met the annual deductible. This is a significant benefit for insulin-dependent individuals who previously might have paid hundreds of dollars for insulin in the early months of the year before meeting their deductible.

What the $35 cap applies to per fill

The cap applies per insulin product per month. If you use a single insulin, you pay no more than $35 for a monthly supply. If you use two different insulins, for example, a long-acting basal insulin and a rapid-acting mealtime insulin, each carries its own $35 cap, for a maximum of $70 per month total for both. Insulin pens, vials, and cartridges of the same insulin product are treated as the same product for purposes of the cap.

Which insulins qualify

The cap applies to insulin that is on your Part D plan formulary. If your specific insulin is covered by the plan, the cap applies. If your insulin is not on the formulary, standard non-formulary cost rules apply, which means you may pay considerably more or the plan may not cover it at all. This is why formulary review before enrollment matters specifically for insulin-dependent individuals, you want to confirm your insulin is covered before selecting a plan.

Taking insulin and want to make sure your Part D plan covers it at the $35 cap?

Not every plan formulary covers every insulin. I can check your specific medications against available plans in your area to find the best fit.

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Over-the-counter insulin is not included

Insulin available over the counter without a prescription, such as ReliOn brand insulin sold at Walmart pharmacies, is not covered by Medicare Part D. Part D covers prescription drugs dispensed at a pharmacy. Since OTC insulin does not require a prescription, it falls outside Part D coverage and the $35 cap does not apply to it. OTC insulin remains an option for uninsured individuals but is not relevant to Part D planning.

Medicare Advantage and the cap

The $35 insulin cap applies equally to Medicare Advantage plans that include Part D drug coverage. Both standalone Part D plans and Medicare Advantage plans with drug coverage are required to implement the cap. If you have a Medicare Advantage plan with drug coverage and you use insulin, the $35 monthly cap applies to your covered insulin products.

Frequently asked questions

Does the $35 cap apply automatically, or do I need to do something to get it?

It applies automatically for covered insulin. No action is required beyond being enrolled in a plan that covers your insulin. The pharmacy applies the cap at the point of sale.

What if I was charged more than $35 for insulin after January 2023?

If you were charged more than $35 per month for a covered insulin product after January 1, 2023, contact your plan to request a reimbursement. Plans are required to implement the cap and should correct billing errors if you were overcharged.

Does the $35 cap also apply to insulin delivery devices like syringes and pens?

The $35 cap applies to the insulin product itself. Insulin pen needles, syringes, and other supplies may be covered separately under Part D or Part B (if considered durable medical equipment in certain contexts) but are not subject to the insulin-specific $35 cap. Their cost-sharing follows normal Part D rules.

Will the $35 insulin cap continue in future years?

The cap was enacted through the Inflation Reduction Act as a permanent provision. Barring future legislative changes, it remains in effect. Check for any policy updates during your Annual Enrollment Period review.

Bryce Casson

Licensed Independent Medicare Broker

Bryce Casson is an independent Medicare insurance broker who works with every major carrier. He does not represent any single insurer, which means his recommendations are based on what actually fits each client's situation, not on commissions or quotas.