Mounjaro is a GLP-1 widely prescribed for type 2 diabetes, and that diagnosis is the key to Medicare coverage. Here is how it works in 2026.
When does Medicare cover Mounjaro?
Medicare Part D may cover Mounjaro (tirzepatide) when it is prescribed to treat type 2 diabetes and your plan lists it on its formulary. The large majority of commercial and Part D plans cover Mounjaro for diabetes. As with other GLP-1 drugs, Medicare cannot pay for it when the only purpose is weight loss; for obesity, the separate 2026 GLP-1 Bridge covers Zepbound, which shares the same active ingredient. Plans often apply prior authorization, step therapy, or quantity limits. A free formulary check at 1-800-MEDIGAP confirms your specific coverage.
What does Mounjaro cost on Medicare in 2026?
When Mounjaro is covered for diabetes, you pay your plan's cost-sharing for its formulary tier, and that spending counts toward the 2026 Part D $2,100 annual out-of-pocket cap. Once you reach $2,100 in covered drug costs, covered prescriptions cost nothing for the rest of the year. Your exact monthly cost depends on plan tier, deductible, and pharmacy. Because plans price the same drug differently, comparing formularies before enrolling can meaningfully lower your cost. Call 1-800-MEDIGAP for a free side-by-side review.