Pharmacy costs are growing faster than any other line item in employer health plan budgets. Prescription drug spending for employer-sponsored health plans is projected to increase by 11 to 12 percent in 2026, well ahead of the already elevated 9 percent medical trend. The primary drivers are GLP-1 medications, specialty drugs, and rising prescription utilization. What many employers do not realize is that the contract governing how their health plan purchases those medications may be making the problem worse. Most mid-size employers have never reviewed that contract.
A pharmacy benefit manager, or PBM, serves as the intermediary between your health plan and the pharmacy supply chain. PBMs negotiate pricing with drug manufacturers and pharmacy networks, manage formularies, and process prescription drug claims. They also generate significant revenue through rebates, spread pricing, administrative fees, and other contract provisions that are not always transparent to employer plan sponsors. In 2026, the difference between what a well-structured PBM contract can deliver and what a typical mid-size employer receives is large enough to have a meaningful impact on renewal costs.

What Most Employers Don’t Know About Their PBM Arrangement
The majority of mid-size employers receive their pharmacy benefit through their medical carrier, bundled into the health plan without a separate PBM contract review. That arrangement is convenient. It is also the structure least likely to deliver strong value for the employer.
Rebates, discounts negotiated between the PBM and drug manufacturers, are one of the largest variables in pharmacy plan economics. In a rebate pass-through model, the full rebate value flows to the employer plan. In a rebate retention model, the PBM keeps a portion or all of the rebate and passes only a contracted amount back to the plan. Most bundled carrier arrangements use some form of retention. According to the International Foundation of Employee Benefit Plans, employers who actively manage their pharmacy benefit through separate carve-out or transparent PBM arrangements consistently achieve better cost outcomes than those who rely on bundled carrier arrangements.
Spread pricing is a related mechanism. A PBM charges the employer plan one amount for a prescription and reimburses the pharmacy a lower amount, keeping the spread as margin. In transparent or pass-through contracts, the employer pays only what the pharmacy is actually reimbursed. The difference between these two structures can be significant at scale.
The Three Levers Most Employers Are Not Pulling
A pharmacy management review before your next renewal should focus on three core areas: rebate transparency (request a full rebate reporting breakdown), formulary performance (a formulary designed around your population’s actual prescription patterns, not the PBM’s preferred manufacturer relationships), and audit rights (a properly structured PBM contract includes the right for the employer to audit claims data and PBM performance). Using data analytics to run a pharmacy claims review before your renewal gives you the baseline to evaluate whether your current PBM arrangement is actually delivering competitive value or whether a carve-out, renegotiation, or vendor change is worth modeling.
Ready to take a hard look at your pharmacy benefit before the next renewal drives the conversation? The team at Tooher-Ferraris has been helping employers control health plan costs since 1932. Contact us today to schedule a no-obligation consultation.




