Mounjaro and Zepbound are both tirzepatide, a weekly injection from Lilly, and the two labels list the same doses in the same four forms: a single-dose pen, a single-dose vial, a multi-dose vial and a KwikPen[1][2]. What separates them is the condition each is approved to treat, and that single difference decides who pays and how much.
| Mounjaro | Zepbound | |
|---|---|---|
| Approved for | Type 2 diabetes (adults and children 10+); heart risk in type 2 diabetes | Weight reduction; moderate to severe sleep apnea with obesity |
| Weekly doses | 2.5 mg to 15 mg | 2.5 mg to 15 mg |
| Self-pay, per month | $499, single-dose pen, every dose | $299–$449, vial or KwikPen, refilled within 45 days |
| Card, plan covers it | As little as $25; up to $150 off a month | As little as $25; up to $100 off a month |
| Card, plan does not | $499 a month | $499 a month, single-dose pen |
What each label covers
Mounjaro is approved to improve blood sugar in adults and children 10 and older with type 2 diabetes[1]. It is also approved to cut the risk of major cardiovascular events in high-risk adults with type 2 diabetes[1]. Zepbound is approved to reduce excess weight and keep it off in adults with obesity, or with overweight and a weight-related condition, and to treat moderate to severe obstructive sleep apnea in adults with obesity[2].
People with diabetes were not left out of Zepbound’s own evidence. SURMOUNT-2 randomized 938 adults with obesity and type 2 diabetes to tirzepatide 10 mg, 15 mg or placebo for 72 weeks[7]. Body weight fell 12.8% and 14.7% on the two doses, against 3.2% on placebo[7]. The trial was funded by Lilly[7].
Paying cash: LillyDirect’s two price lists
Mounjaro’s self-pay price on LillyDirect is $499 a month for the single-dose pen, the same at every dose[3]. Zepbound’s runs from $299 at 2.5 mg to $449 at the higher doses, for a vial or a KwikPen, as long as each refill lands within 45 days[4]. At 15 mg, that puts Mounjaro $50 a month above Zepbound.
Miss Zepbound’s refill window and the higher doses climb to as much as $699[4]. A month on Lilly’s Zepbound list is 28 days[4], so a year of refills is thirteen fills, not twelve. The full ladder, including the late-refill prices, is in Zepbound price, and the Mounjaro side is in Mounjaro cost.
With insurance: the label decides
Health plans have generally covered GLP-1 drugs prescribed for diabetes, KFF reported in its 2025 employer survey[8]. Coverage for weight loss is a separate choice: 16% of firms with 200 to 999 workers covered these drugs primarily for weight loss, rising to 43% at 5,000 or more[8]. A Mounjaro prescription for diabetes and a Zepbound prescription for weight can therefore meet very different answers from the same plan.
Each brand has its own card. With a plan that covers the drug, both can bring a fill down to $25, but Mounjaro’s card caps savings at $150 a month and Zepbound’s at $100[5][6]. Both cards end December 31, 2026 and exclude Medicare, Medicaid and other government plans[5][6]. The Zepbound card’s tiers are set out in Zepbound savings card.
Medicare
Part D plans pay for Mounjaro as a diabetes drug; one study of every Part D formulary found injectable tirzepatide listed by 92.9% of plans, weighted by enrollment, in the third quarter of 2024[9]. By then 83.2% of those plans required prior authorization[9]. Zepbound’s Medicare route runs through its sleep apnea indication and the temporary GLP-1 Bridge, covered in does Medicare cover Zepbound.
Compounded tirzepatide
Compounded tirzepatide is neither brand. It is not FDA-approved, and pharmacies may only make it under narrow rules. How it prices against Zepbound is set out in compounded tirzepatide vs Zepbound, each seller’s month is on the tirzepatide price board, and the no-membership sellers board lists those that charge no monthly membership on top. To test a quote you were given, the seller price check shows how many sellers charge less.
One question settles most of this before any price does: ask your prescriber which condition the prescription will name, then ask your plan whether that brand is on its formulary for that condition.