Methimazole is the cheap end of thyroid care. Medicare Part D covered 943,504 methimazole claims for 220,650 people in 2024 at an average of $11.24 per claim, and a pharmacy pays seven cents for a 5 mg tablet. If you are uninsured and staring at an overactive thyroid diagnosis, the medication is very unlikely to be the expensive part.
What can still go wrong is filling it at the wrong counter, or being handed a prescription for brand Tapazole, which has been discontinued for years but is still price-listed at more than thirty times the generic. Every figure below was researched on September 4, 2026.
What Does Methimazole Cost Without Insurance?
Acquisition costs are from the CMS National Average Drug Acquisition Cost survey, rows effective August 19, 2026. Cash prices come from Cost Plus Drugs, Drugs.com and HealthWarehouse, all read September 4, 2026. Cost Plus quotes on a 30-count basis and adds $5.00 flat standard shipping at checkout.
| Option | Low | Average | High |
|---|---|---|---|
| CMS NADAC acquisition cost, one methimazole tablet | $0.07073 (5 mg) | $0.09768 | $0.12463 (10 mg) |
| Cost Plus Drugs, 30 tablets (plus $5.00 shipping) | $6.38 (5 mg) | $6.93 | $7.48 (10 mg) |
| HealthWarehouse, 30 tablets | $10.50 (5 mg) | $15.90 | $21.30 (10 mg) |
| HealthWarehouse, 90 tablets | $28.80 (5 mg) | $37.35 | $45.90 (10 mg) |
| Drugs.com cash price, 90 tablets | $12.81 (5 mg) | $15.46 | $18.11 (10 mg) |
| Retail comparison price, 30 tablets, no program | $18.30 (5 mg) | $20.70 | $23.10 (10 mg) |
| Medicare Part D 2024 average, methimazole | $11.24 per claim | $11.24 per claim | $11.24 per claim |
| Propylthiouracil 50 mg, 30 tablets, cash | $10.04 (Cost Plus) | $15.30 (HealthWarehouse) | $17.70 (Drugs.com) |
| Brand Tapazole, 100 tablets (discontinued product) | $224.14 (5 mg) | $302.26 | $380.37 (10 mg) |
The working range for most people is $6 to $21 for 30 tablets. The Cost Plus figures are the cheapest published prices we found, and even with $5.00 shipping added the 5 mg lands at $11.38 delivered, still below the $18.30 retail benchmark Cost Plus itself shows on the same page.
The one figure to treat carefully is the Tapazole row. It is a real published price on a live page, but for a product FDA lists as discontinued at every strength.
What Drives the Price
Strength, and only two of them exist
Methimazole is marketed in the United States as a 5 mg and a 10 mg tablet, and nothing else. CMS surveys exactly those two descriptions. The 10 mg costs a pharmacy 76% more than the 5 mg ($0.12463 against $0.07073), and that gap widens at retail: HealthWarehouse charges twice as much for the 10 mg 30-count as for the 5 mg.
Which pharmacy you use
This is the whole story on a drug this cheap. Thirty tablets of the 10 mg cost $7.48 at Cost Plus and $21.30 at HealthWarehouse, a 2.8x spread on a product whose ingredient cost is $3.74. Neither pharmacy is doing anything unusual; the dollar amounts are small enough that fixed dispensing costs dominate. Cost Plus publishes its formula openly: manufacturing cost, a 15% markup, and a $5.00 flat pharmacy labor fee.
Package size
Buying 90 at a time cuts the per-tablet price meaningfully. HealthWarehouse’s 5 mg runs $0.35 per tablet at 30 count and $0.32 at 90, and $0.29 at 180. Drugs.com’s 5 mg falls from $0.14 per tablet at 90 count to $0.10 at 500.
There is no brand competition left
Tapazole, the original brand, is gone. Drugs@FDA lists both strengths under King Pharmaceuticals’ NDA 007517 and the companion ANDA 040320 as Discontinued, annotated with the standard note that the product was not discontinued or withdrawn for safety or effectiveness reasons. It has no rows at all in the CMS acquisition file and no Medicare Part D claims in 2024. Meanwhile FDA’s National Drug Code Directory lists 53 active methimazole packages, all filed as ANDAs, which is why the generic price is what it is.
If a prescription comes back written for Tapazole by name, that is worth a call to the prescribing office before you pay anything.
Which antithyroid drug you were prescribed
Propylthiouracil is the other option and it costs more. A 50 mg tablet is $0.27009 in the August 19, 2026 CMS file against $0.07073 for methimazole 5 mg. Cost Plus charges $10.04 for 30 against $6.38. The gap is widest at the prescription level: Medicare Part D averaged $56.26 per propylthiouracil claim in 2024 against $11.24 for methimazole, because propylthiouracil prescriptions carry far more tablets. Which drug is appropriate is entirely a clinical question, and not one this page can answer.
Cash Price vs. Insurance
Methimazole is a drug where cash beats a copay more often than not. Medicare Part D’s 2024 all-in average was $11.24 per claim, and a $10 or $15 commercial copay is common. Cost Plus at $6.38 to $7.48 for 30 tablets undercuts both.
That also means running methimazole through insurance is often pointless. If you have a deductible you have not met, the pharmacy is charging you the plan’s contracted rate anyway, and you are just as well off asking for the cash price. Ask both ways at the counter and take the lower one. Nothing prevents you from doing this, and the pharmacy is not obligated to volunteer it.
There is no manufacturer program to fall back on either. Drugs.com’s price guide states that no manufacturer promotions could be found for methimazole and that no patient assistance programs were found for it, and the same two lines appear on the Tapazole page. This is a drug with no coupon economy at all, which in practice is good news: the published prices are the real prices.
How to Pay Less
Start with Cost Plus Drugs. At $6.38 for 30 of the 5 mg and $7.48 for 30 of the 10 mg, plus $5.00 flat shipping, it was the cheapest published price we found by a wide margin. Order a 90-day supply in one shipment and the $5.00 stops mattering. Cost Plus does not accept insurance, which is exactly why it is priced this way.
Compare the counter price at your regular pharmacy anyway. The 2.8x spread we measured between two legitimate mail pharmacies means local prices are worth one phone call. Our fair price checker will tell you whether a quote is inside the range above, and our GoodRx vs. SingleCare guide explains what a discount card actually changes on a drug this cheap (usually less than people expect).
Ask for 90 days instead of 30. Every source we read prices the 90-count below three 30-counts. HealthWarehouse’s 5 mg goes from $10.50 for 30 to $28.80 for 90, and to $52.20 for 180 at $0.29 per tablet.
Check the prescription for the brand name. Tapazole is a discontinued product still carrying $224 to $380 per 100 list prices. If your prescription says Tapazole rather than methimazole, ask the prescribing office to rewrite it before you fill anything.
Do not spend time hunting a coupon. There is none, from any manufacturer, and there is no patient assistance program. The Walmart $4 list does not include methimazole, propylthiouracil or Tapazole at any tier, verified against all three pages of the 03/24/2025 program document.
Budget the monitoring, not the pills. Antithyroid treatment involves repeated lab work, and that is where uninsured patients actually get hurt. See thyroid test cost for cash lab prices, free and sliding-scale clinics for income-based visit pricing, and hospital charity care if a hospital-based endocrinology bill is already in hand.
The Bottom Line
Methimazole is a $6 to $21 per 30 tablets cash prescription in September 2026, and the difference between the top and the bottom of that range is entirely which pharmacy you walk into. There is no coupon, no assistance program, and no brand competitor still on the market, so the only lever that works is comparison shopping and buying in 90-day quantities.
If your thyroid prescription runs the other direction, toward replacement rather than suppression, see levothyroxine cost for the most-dispensed option and Armour Thyroid cost or NP Thyroid cost for the desiccated products, which are 10 to 30 times more expensive per tablet.