Generic metformin is one of the most affordable prescription medications available. A 30-day supply of the standard 500mg tablet starts around $5 to $8 without insurance, and discount coupons can drop the price to as little as $2.75 for 60 tablets. Even at the full retail price, you’re rarely looking at more than $10 to $15 per month for the most common dosages.
Cost by Dosage
Metformin comes in several strengths, and the price differences between them are surprisingly small. For a 30-day supply of immediate-release tablets without insurance or coupons, here’s what to expect:
- 500mg: $5.42 to $7.47
- 850mg: $5.69 to $9.48
- 1000mg: $5.58 to $8.61
The per-tablet cost hovers between roughly $0.18 and $0.32 regardless of strength. If your doctor increases your dose from 500mg to 1000mg, your monthly cost stays nearly the same because the higher-strength tablets cost about the same per pill as the lower ones.
Extended-Release vs. Immediate-Release
Extended-release (ER) metformin, which you take once daily instead of two or three times, costs a bit more. A 30-day supply of 500mg ER tablets runs about $7 to $8, and the 750mg ER version starts around $9.63 for 30 tablets. That’s roughly $2 to $3 more per month compared to the immediate-release form at similar strengths.
For most people, the price gap is small enough that it comes down to preference and how your body tolerates each version. ER formulations tend to cause fewer stomach side effects, which is the main reason doctors prescribe them.
Saving More With 90-Day Supplies
Filling a 90-day supply instead of three separate monthly fills cuts your per-tablet cost nearly in half. For 500mg immediate-release tablets, the price drops from about $0.18 to $0.25 per tablet down to $0.09 to $0.12 per tablet when you buy 90 at once. A full 90-day supply of 500mg tablets runs $7.75 to $10.49, compared to roughly $16 to $22 if you filled three separate 30-day prescriptions.
The same pattern holds for higher dosages. Ninety tablets of 1000mg cost $9.04 to $10.24, bringing the per-tablet price to about $0.10. If your pharmacy and insurance allow 90-day fills, it’s consistently the cheaper option.
Prices at Major Pharmacies
Where you fill your prescription matters. Using a free discount coupon from services like GoodRx, prices for 60 tablets of metformin 500mg vary significantly by pharmacy:
- Walgreens: $8.33
- Walmart: $9.00
- Sam’s Club: $9.82
- CVS Pharmacy: $17.13
Without any coupon, the average retail price for that same quantity is around $43, though almost nobody pays that. Discount cards, store programs, and insurance all bring the cost down dramatically. The lowest coupon prices can hit $2.75 for 60 tablets at certain pharmacies, a 90% discount off retail.
Liquid Metformin Costs Significantly More
If you or your child can’t swallow tablets, metformin also comes as an oral solution (brand name Riomet). This formulation is far more expensive. A 300ml bottle, which contains the equivalent of about a month’s supply at a standard dose, retails for roughly $306. Even with a discount coupon, the price sits around $96.
That’s a steep jump from $5 to $10 for the tablet form. If cost is a concern, some people work with their pharmacist to explore whether splitting or crushing tablets is an option for their specific prescription.
What You’ll Actually Pay With Insurance
Most insurance plans, including Medicare Part D and Medicaid, cover generic metformin as a preferred drug. Copays typically fall between $0 and $10 for a 30-day supply, and many plans cover it at $0 because it sits on the lowest formulary tier. If your copay is higher than $10, a free pharmacy discount coupon may actually beat your insurance price, so it’s worth comparing both before you pay.
Metformin has been generic for decades and is on the World Health Organization’s list of essential medicines, which keeps competition high and prices low. Unlike many diabetes medications that can cost hundreds per month, metformin remains one of the most budget-friendly options available.