The same medication, the same quantity and the same insurance can produce different amounts at two pharmacies a few blocks apart. There is no single price for a prescription drug in the United States, and the reason is contractual.
There is no published price to reference
Most consumer goods have a price set by the seller. A prescription drug has a chain of separately negotiated prices between manufacturers, wholesalers, pharmacies, insurers and intermediaries.
Each of those agreements is confidential, and none of them is the number the patient sees.
What a patient pays is the output of whichever contracts happen to apply to that pharmacy, that plan and that drug on that day.
Benefit managers sit between plan and pharmacy
Insurers typically contract with pharmacy benefit managers to administer drug coverage, build formularies and negotiate with pharmacies.
The benefit manager agrees separate reimbursement terms with each pharmacy chain, so two pharmacies dispensing the same medication may be reimbursed differently.
Formulary placement then determines which tier a drug sits in, which sets the patient's share.
Rebates move money after the sale
Manufacturers offer rebates to secure favourable formulary placement, paid after the prescription is dispensed.
Because those rebates flow between manufacturer, benefit manager and plan, the amount a patient pays at the counter may be calculated on a price that nobody in the chain ultimately keeps.
This is why a coinsurance amount can be based on a figure higher than the net cost of the medicine.
Cash prices follow a separate track
A pharmacy also sets a price for customers not using insurance, and discount card programmes negotiate their own rates on top of that.
For some generic medications the cash or discount price is lower than the insured amount, which is why pharmacists are sometimes able to offer a cheaper route.
Rules preventing pharmacists from mentioning this were addressed by federal legislation, so asking directly is now a reasonable step.
Comparison is possible but has to be deliberate
Prices at nearby pharmacies for the same generic drug can differ substantially, and the only way to establish that is to call or check each one.
Transferring a prescription is straightforward, and mail order through a plan's preferred pharmacy is frequently priced differently again.
The variation is not an error in the system. It is what a market with confidential prices and multiple intermediaries produces at the counter.