A Pharmacy Benefits Calculator reads in an insured's prior pharmacy claims history and then calculates said insured's anticipated out-of-pocket costs for one or more pharmacy benefits plans that said insured is eligible to enroll in. Provision is made for an insured to modify their anticipated future pharmacy needs. Provision is also made for an insured to compare their out-of-pocket costs for different alternative drugs, said alternative drugs providing comparable therapeutic benefits. Provision also is made for an insured to substitute a lower cost generic equivalent for a brand drug, when available. Another provision is made for an insured to choose to price drugs at a retail pharmacy store or a mail order pharmacy and determine cost differences. The pricing available from said retail pharmacy store may be based on a price negotiated by an insurance company offering said pharmacy benefits plans.