Retatrutide Cost: $10/mg at 10 mg, $9.75 at 20 mg
A 10 mg retatrutide vial at $100 is $10.00/mg; the 20 mg vial at $195 drops to $9.75/mg. Full per-mg and per-vial breakdown, as of September 2026.
Reviewed by Marcus Webb, PhD, research pharmacologist ·
Marcus Webb, PhD is a research pharmacologist with a doctorate from Johns Hopkins University and over 12 years of experience in receptor-selective peptide analogs, bioavailability science, and the pharmacoeconomics of emerging therapeutic compounds.
- retatrutide
- pricing
- cost-per-mg
A 10 mg retatrutide vial listed at $100 works out to $10.00 per mg. A 20 mg vial at $195 works out to $9.75 per mg, a 2.5% reduction (catalog prices as of September 2026). That division is the whole of retatrutide cost at the vial level: take the listed price, divide by the labeled milligrams, and compare the quotients rather than the sticker prices. The larger format is cheaper per mg on paper. Whether it is cheaper in practice depends on how much of the last vial goes unused.
What does retatrutide cost per mg by vial size?
| Vial size (mg) | Listed price (USD) | Price per mg (USD) | Change vs 10 mg |
|---|---|---|---|
| 10 | $100 | $10.00 | baseline |
| 20 | $195 | $9.75 | -$0.25 (-2.5%) |
Retatrutide vial prices and the per-mg figure derived from them. Prices from the HEEZ Research catalog, as of September 2026. Per-mg column is listed price ÷ labeled mg ($100 ÷ 10 = $10.00; $195 ÷ 20 = $9.75).
The spread between the two formats is $0.25 per mg, which is smaller than it sounds. You would have to buy 400 mg of material at the 20 mg rate before that discount accumulates to the price of a single 10 mg vial ($100 ÷ $0.25 = 400 mg). Anyone treating the larger vial as a substantial saving is overestimating it by a wide margin.
Two inputs drive every figure above, and both have to come off the same listing: the labeled milligram content of the vial and the total price a buyer actually pays. On this retatrutide product listing both numbers are stated per size option, which is the format that makes the division checkable. A listing that gives a per-mg figure without stating vial content leaves you no way to verify it.
Is a 20 mg vial cheaper than two 10 mg vials?
Yes, by $5. Two 10 mg vials cost 2 × $100 = $200 for 20 mg of material. One 20 mg vial costs $195 for the same 20 mg. The saving is 2.5% of the two-vial price, consistent with the per-mg gap in the table above.
That is the entire bulk effect available between these two sizes. It runs in the direction bulk vial pricing patterns usually run, but the magnitude is modest, and a shipping charge applied to one order and waived on the other would erase it.
What do the vial formats cost once you count whole vials?
Vials are not divisible at the point of purchase, so the real question is what a given total milligram figure costs after rounding up to whole units. The published phase 2 dose arms supply four concrete totals to test that against.
That trial enrolled 338 adults and dosed subcutaneous retatrutide once weekly at 1 mg, 4 mg, 8 mg or 12 mg for 48 weeks (Jastreboff et al., NEJM 2023, phase 2 retatrutide obesity trial). Its primary endpoint was percentage change in body weight from baseline to 24 weeks, where the same report gives least-squares mean changes of -7.2% (1 mg), -12.9% (combined 4 mg), -17.3% (combined 8 mg) and -17.5% (12 mg) against -1.6% for placebo.
Those four weekly doses are what the milligram totals below are built from, at 48 weeks each.
| Phase 2 dose arm | Total mg (dose × 48 wk) | 10 mg vials | Cost via 10 mg | 20 mg vials | Cost via 20 mg | Cheaper format |
|---|---|---|---|---|---|---|
| 1 mg/wk | 48 | 5 | $500 ($10.42/mg) | 3 | $585 ($12.19/mg) | 10 mg |
| 4 mg/wk | 192 | 20 | $2,000 ($10.42/mg) | 10 | $1,950 ($10.16/mg) | 20 mg |
| 8 mg/wk | 384 | 39 | $3,900 ($10.16/mg) | 20 | $3,900 ($10.16/mg) | tie |
| 12 mg/wk | 576 | 58 | $5,800 ($10.07/mg) | 29 | $5,655 ($9.82/mg) | 20 mg |
Whole-vial purchase cost for the total material in each phase 2 dose arm. Dose arms and the 48-week duration come from the NEJM 2023 phase 2 trial linked above (PMID 37366315); vial prices from the HEEZ Research catalog as of September 2026. Total mg = weekly dose × 48. Vial count = total mg ÷ vial size, rounded up to a whole vial. Effective $/mg = total cost ÷ total mg.
Read the first row before the last one. At 48 mg of material, the 20 mg vial is the more expensive route by $85, because three vials deliver 60 mg and 12 mg of that is surplus. Effective cost lands at $585 ÷ 48 = $12.19/mg, well above the 10 mg vial’s $500 ÷ 48 = $10.42/mg. The format with the better headline per-mg price is the worse buy at that volume.
The 8 mg row is a genuine tie at $3,900 by either route (39 × $100 and 20 × $195 both equal $3,900). Only at the 576 mg total does the 20 mg format pull clearly ahead, saving $145.
So the position is this: the 20 mg vial’s $0.25/mg advantage is real but thin, and whole-vial rounding moves effective cost by up to $2.44/mg in the cases above. Total milligrams, not the headline per-mg figure, decides which format is cheaper. Working out that total first is the step budgeting a multi-week protocol turns on.
Why is there no retail price to compare against?
Retatrutide is investigational, not an approved product, so no pharmacy or list price exists for it. Development has moved into the TRIUMPH program: four phase 3 multicentre randomised double-blind studies of weekly subcutaneous retatrutide against placebo, enrolling over 5,800 participants across obesity, obstructive sleep apnea and knee osteoarthritis protocols (Giblin et al., Diabetes Obes Metab 2026, TRIUMPH trial design).
Until that program produces an approved product, research-catalog listings are the only per-mg reference points that exist, and material sold on them is for research use only. That also explains the price variance: with no reference price anchoring the category, each seller sets vial prices independently.
What makes two listings’ per-mg figures non-comparable?
- Bundle totals presented as vial content. A $380 listing for “2 × 20 mg” is $9.50/mg, but only if you divide by 40, not 20. Check which number the seller divided by.
- Shipping treatment. A $195 vial with $25 shipping is $11.00/mg, not $9.75/mg (($195 + $25) ÷ 20 = $11.00). Compare listings on the same basis or not at all.
- Concentration confused with cost. Milligrams per mL after reconstitution is a dilution figure and does not change what the vial cost. The distinction is covered in per-mg cost versus vial concentration.
- Minimum order quantities. A per-mg price quoted at a 5-vial minimum is not the price of one vial.
What should a retatrutide price quote state?
- Labeled milligram content per vial, as a number, not a size name.
- Price per vial, with the quantity that price applies to.
- Whether shipping and handling are included in that figure.
- The date the price was quoted, since catalog prices move between revisions.
- Batch or lot identification, so the purity documentation can be matched to what ships.
With items 1 and 2 present you can reproduce the per-mg figure yourself; with item 3 you can compare it to another seller’s. Turning that per-mg figure into a per-dose cost from vial price is a separate calculation that depends on how the vial is prepared.
If a listing states a per-mg number but withholds the labeled vial content, the number cannot be checked. An unverifiable $9.75/mg is worth less than a verifiable $10.00/mg.