Which Pharmacy Charges the Least?
Not all pharmacies charge the same price for the same prescription. The difference can be dramatic: Walmart, Costco, and Sam's Club consistently price generics the lowest — often $4 to $10 per 30-day supply on hundreds of common medications with no discount card required. CVS and Walgreens tend to charge higher retail prices, but applying a free discount card often brings them much closer to Walmart pricing.
Costco pharmacy is open to non-members in most states for pharmacy visits, making it a widely accessible low-price option. Independent pharmacies vary widely — some are surprisingly competitive, particularly for specialty or compounded medications. Mail-order pharmacies (including those run by CVS Caremark, Express Scripts, and OptumRx) often offer the best pricing on 90-day supplies for maintenance medications.
The best pharmacy for your prescription depends on three variables: the specific drug, your dosage and quantity, and your ZIP code. A pharmacy that's cheapest for metformin may be more expensive for gabapentin. This is why RxDiff compares prices at every nearby pharmacy location before you fill — you see the real price at each option, with and without a discount card, so you can make an informed choice.
Our pharmacy comparison guides document real price differences across the major chains for the most commonly filled medications, with actual price data so you know what to expect before walking in.