Under a traditional spread arrangement, the amount billed to the employer for the drug dispensed by the pharmacy is not necessarily the same amount the PBM pays the pharmacy. The difference is the spread, which the PBM retains as revenue. Most arrangements in place today apply some level of traditional spread pricing. In general, the discounts in a traditional spread arrangement typically perform very close to the minimum levels guaranteed by the PBM.
By contrast, with a pass-through arrangement, the employer pays the actual contracted discounted pharmacy prices and dispensing fees that the PBM has negotiated with the retail pharmacy network. The guaranteed discount in a pass through proposal should be viewed by the employer as a minimum acceptable performance level, although higher discounts than those guaranteed are often achieved.