Costco sells generic emergency contraception for around $6 to $7, compared to $40 to $50 for brand-name Plan B One-Step at most drugstores. The reason comes down to three things: Costco sells the generic version of the drug, operates on razor-thin pharmacy margins as a business model, and keeps the product behind the pharmacy counter where lower-overhead generics are common.
Generic vs. Brand Name Explains Most of the Gap
The biggest factor isn’t anything unique about Costco’s business. It’s that the $6 product and the $50 product contain the exact same active ingredient: 1.5 mg of levonorgestrel. Plan B One-Step is a brand name. The generic version works identically, and the FDA requires manufacturers to prove it through bioequivalence testing, meaning the generic must deliver the same amount of the drug into the bloodstream at the same rate as the branded version. The only differences are packaging, branding, and price.
At Costco, the generic levonorgestrel tablet typically costs around $5.99. Brand-name Plan B One-Step at the same Costco runs about $36.99. At CVS or a typical drugstore, the brand name often hits $50, and even generics can cost $25 to $40 depending on the store and which generic brand they stock. So part of what makes Costco look dramatically cheaper is that many people are comparing a Costco generic to a drugstore brand-name product.
Costco’s Pharmacy Pricing Model
Even comparing generic to generic, Costco tends to undercut other pharmacies. GoodRx data from 2025 shows generic levonorgestrel at Costco priced around $18.71 at standard retail, while Walgreens lists it at similar prices before coupons. But Costco’s behind-the-counter generic at $5.99 is a different product listing, one that other chains either don’t stock or don’t prioritize because the margins are tiny.
Costco’s entire business model helps explain this. The company makes most of its profit from membership fees, not from markups on individual products. That extends to the pharmacy, where Costco consistently ranks among the lowest-cost options in the country. The warehouse doesn’t need to make significant profit on each pill sold because the pharmacy exists partly to drive membership value. Traditional drugstores like CVS and Walgreens rely heavily on product markups for revenue, which pushes prices higher across the board.
You Don’t Need a Membership
One detail that surprises many people: you don’t need a Costco membership to use the pharmacy. Federal and state pharmacy regulations in most states prevent warehouse clubs from restricting prescription drug access to members only. Costco confirms this on their customer service page, stating that non-members can purchase from the pharmacy counter both in-store and online. You can pay with cash, debit cards, or Visa.
Because emergency contraception is available without a prescription for all ages, you can walk into a Costco pharmacy without a membership card and buy the generic for around $6. You won’t need to scan a membership card at the pharmacy counter, which also offers a degree of privacy that some buyers value.
Why Drugstore Prices Stay High
The more interesting question might be why other stores charge so much. Several factors keep drugstore prices elevated. First, many chain pharmacies prominently stock the brand-name Plan B One-Step on shelves or behind the counter, and brand-name manufacturers set higher prices to recoup marketing and development costs. Second, pharmacies in high-traffic urban locations have significantly higher overhead costs than a Costco warehouse on the edge of town. Third, convenience pricing plays a role. Emergency contraception is a time-sensitive purchase, and stores know that someone who needs it at 11 p.m. on a Saturday isn’t comparison shopping.
The wholesale cost of generic levonorgestrel is remarkably low. Pharmacy acquisition costs reported by industry trackers sit around $5 to $6.40 per tablet, meaning Costco’s $5.99 price point barely clears their own cost. A store charging $25 to $40 for the same generic tablet is adding a substantial markup, which is standard practice in retail pharmacy but feels stark when you see the Costco price.
Where to Find It in the Store
At most Costco locations, the generic levonorgestrel is kept behind the pharmacy counter rather than on open shelves. You’ll need to ask for it directly. Some warehouses also stock the brand-name Plan B One-Step, but the generic is the one priced at roughly $6. There’s typically a limit of two per purchase. The pharmacy counter operates during set hours, so if you’re going specifically for this, check your local Costco’s pharmacy schedule, as it’s usually shorter than the warehouse’s general hours and closed on Sundays at many locations.
For comparison, other low-cost options include certain grocery store pharmacies, where GoodRx data shows prices as low as $8 to $10 with coupons. Amazon also carries generic emergency contraception at varying prices. But for a walk-in, no-coupon, no-membership purchase, Costco’s pharmacy counter remains one of the cheapest reliable options available.