Metformin is the most commonly prescribed first-line treatment for type 2 diabetes in the United States — and one of the most affordable generic medications available. But even for an inexpensive drug like metformin, pharmacy prices vary significantly. This guide shows you where to find the cheapest pharmacy for metformin, what affects the metformin cost without insurance, and how to compare metformin prices to find the best deal in 2026.
Use RxDiff's metformin price comparison tool to compare current pricing at pharmacies near you.
Medical disclaimer: RxDiff brand content. This article is for informational purposes only. Metformin is a prescription medication. Always tell your doctor about all medications you take and follow your healthcare provider's instructions. Not valid with Medicare or Medicaid. Cannot be used simultaneously with insurance.
What Is Metformin and What Is It Used For?
Metformin is an oral biguanide medication used as the first-line treatment for type 2 diabetes. It helps control blood sugar levels by reducing the amount of sugar made by the liver, improving the body's response to insulin, and slowing the absorption of sugar from food. Metformin works most effectively when combined with a healthy diet and exercise.
Metformin is available as generic metformin (the most common form) and under the brand name Glucophage. Generic metformin has the same active ingredient and works the same way as the brand-name version, but costs a fraction of the price. Metformin is available in immediate-release and extended-release (metformin ER) tablet formulations, taken one to three times daily depending on the dosage and formulation.
Common side effects of metformin include nausea, diarrhea, stomach pain, and dizziness — usually manageable by starting at a low dose and gradually increasing. A rare but serious risk is lactic acidosis (a buildup of lactic acid in the blood), which is more likely in patients with kidney problems. Always tell your doctor about all your medical conditions before taking metformin, and get medical help right away if you experience symptoms of lactic acidosis such as weakness, rapid breathing, or stomach pain.
Metformin Cost Without Insurance — 2026 Data
| Formulation | Dose | Quantity | Retail Price | Coupon Price* |
|---|---|---|---|---|
| Generic metformin IR | 500 mg | 60 tablets (30-day) | $4–$12 | ~$2–$8 |
| Generic metformin IR | 1000 mg | 60 tablets (30-day) | $5–$15 | ~$3–$10 |
| Generic metformin ER | 500 mg | 30 tablets (30-day) | $6–$18 | ~$4–$12 |
| Generic metformin ER | 750 mg | 30 tablets (30-day) | $8–$22 | ~$5–$14 |
| Any form | Any dose | 90-day supply | $10–$40 | ~$6–$25 |
*Prices approximate. The cost of metformin can vary depending on the pharmacy. Always compare metformin prices at RxDiff before filling.
Compare Metformin Prices at Major Pharmacies
| Pharmacy | 500 mg, 60 tablets (retail) | With coupon* | Notes |
|---|---|---|---|
| Walmart Pharmacy | $4 | ~$4 | $4 generic list — may not need coupon |
| Costco Pharmacy | $5–$10 | ~$4–$8 | Competitive cash pricing — open to non-members |
| Kroger Pharmacy | $5–$12 | ~$4–$9 | Often competitive on generics |
| CVS Pharmacy | $10–$20 | ~$4–$10 | Coupon significantly reduces price |
| Walgreens | $12–$22 | ~$5–$12 | Coupon significantly reduces price |
*Coupon prices approximate. Pharmacy prices vary by location. Find the best price for your location at RxDiff.
How to Find the Cheapest Pharmacy for Metformin
Walmart Pharmacy's $4 generic program often includes metformin at standard doses. This may be the cheapest pharmacy for metformin without needing any coupon or discount card.
Use RxDiff to find the best price at all pharmacies near you in one search — including coupon prices at CVS, Walgreens, Costco, and Kroger.
A 90-day supply of metformin typically costs less per tablet than three separate 30-day fills. Ask your doctor to write a 90-day prescription if you are on a stable dosage.
Mail-order pharmacies often offer the lowest per-tablet cost for maintenance medications like metformin, plus the convenience of home delivery. Ask your insurance plan about covered mail-order options.
Is Metformin Covered by Insurance?
Yes — metformin is covered by virtually all commercial health insurance plans, Medicare Part D, and Medicaid as a preferred generic (Tier 1) medication, typically with a very low or no copay. Because metformin is the first-line treatment for type 2 diabetes and one of the most prescribed generic drugs in the United States, insurance plans consistently cover it at the lowest cost tier.
Even if you have insurance that covers metformin with a low copay, it is worth comparing your copay against the discount card cash price. For many patients, the RxDiff coupon price for metformin is lower than their insurance copay — particularly at Walmart where the cash price may be as low as $4.
Metformin Home Delivery — Mail-Order Options
Many insurance plans offer mail-order pharmacy services for maintenance medications like metformin, often at a lower cost per fill than retail pharmacy prices. Home delivery of metformin through mail-order pharmacies typically provides a 90-day supply at a lower total cost than three separate 30-day retail fills.
If home delivery is a priority, ask your insurance plan whether mail-order is available and covered for metformin. Some plans require mail-order after a certain number of retail fills for maintenance medications. Online pharmacies that are properly licensed and verified may also offer competitive metformin prices with home delivery — always verify the pharmacy's legitimacy before purchasing prescription medications online.
Metformin for Weight Loss — What the Research Shows
Metformin is not FDA-approved for weight loss, but clinical research suggests it may support modest weight loss as a secondary effect of improved insulin sensitivity and reduced appetite in some patients with type 2 diabetes. The weight loss effect of metformin is generally modest compared to dedicated weight management medications.
If you are considering metformin for weight loss purposes, talk with your doctor about whether it is appropriate for your specific situation. Metformin works most effectively for blood sugar control when combined with a healthy diet and exercise — effects that also support weight management.
Patient Assistance Programs for Metformin
Because generic metformin is already so affordable, formal manufacturer patient assistance programs are less common than for expensive brand-name drugs. However, several programs may help if cost is still a barrier:
Community health clinics: Federally qualified health centers and community health centers provide prescription services at reduced cost for uninsured and low-income patients, including metformin and other diabetes medications.
State pharmaceutical assistance programs: Some states offer programs that help low-income residents with prescription costs. Contact your state health department or call 1-800-MEDICARE for referrals to programs in your area.
FAQ — Cheapest Pharmacy for Metformin
Walmart Pharmacy often has the cheapest metformin price, frequently listing standard doses on its $4 generic program. Costco, Kroger, and grocery store pharmacies are also often cheaper than major drug chains. The best price depends on your location and specific dosage — use RxDiff to compare current metformin prices at all pharmacies near you.
Generic metformin typically costs $4–$15 per month without insurance for a standard 30-day supply, depending on the dose and pharmacy. At Walmart, metformin may be available for $4. With a discount coupon, prices at most major chains are typically $4–$10 for 500 mg. Compare current prices at RxDiff.
Yes — metformin is covered by virtually all commercial insurance plans, Medicare Part D, and Medicaid as a preferred generic medication, typically with a very low copay. Compare your insurance copay against the discount card price — for metformin, the cash price is often lower than even a low copay.
Metformin is not FDA-approved for weight loss, but some research suggests modest weight loss may occur as a secondary effect in people with type 2 diabetes. Talk with your doctor for medical advice about whether metformin is appropriate for your specific situation and treatment goals.
Find the Cheapest Pharmacy for Metformin Near You
Use RxDiff's metformin comparison page to find the best price at 70,000+ pharmacies — free, no account needed.
Compare Metformin PricesNot valid with Medicare or Medicaid. Cannot be used simultaneously with insurance. Prices vary by pharmacy, dose, and quantity.