For employers managing pharmacy benefits, the structure of a pharmacy network has a direct impact on what members pay, where they can fill prescriptions, and how well the plan controls costs. Yet pharmacy networks are often treated as background infrastructure (something the PBM handles) rather than a strategic decision that deserves active oversight.
Understanding how networks are structured, and what changes to watch for, helps plan sponsors make more informed decisions and avoid costly surprises.
What Is a Pharmacy Network?
A pharmacy network is a group of pharmacies that have agreed to dispense medications to plan members at contracted rates. Networks vary in size and composition, but they typically include retail chains, independent pharmacies, mail order services, and specialty pharmacies.
The PBM builds and manages these networks on behalf of insurers and employers. PBMs negotiate dispensing rates with pharmacies, set credentialing standards, and determine which pharmacies qualify for which network tiers.
How Networks Are Structured
Not all pharmacies in a network operate on equal terms. Most plans use a tiered structure that influences member cost-sharing and access:
- Preferred pharmacies have agreed to lower dispensing fees. Members who fill at preferred pharmacies typically pay lower copays or coinsurance. In some cases, preferred pharmacies are the only option for 90-day supplies, which are commonly used for maintenance medications.
- Standard network pharmacies are in-network but carry higher member cost-sharing. Members can fill there, but the plan and member both pay more compared to the preferred tier.
- Out-of-network pharmacies are not contracted with the plan. If a member fills at an out-of-network location, insurance typically does not cover the cost, and the member pays the full price out of pocket.
Plans may also implement exclusive arrangements. For example, requiring members to fill maintenance medications exclusively through mail order, or designating a single specialty pharmacy for certain high-cost drug categories.
Why Network Design Matters for Plan Sponsors
The way a network is structured affects plan performance in ways that go beyond simple access.
- Cost exposure. Directing members to preferred pharmacies lowers per-claim costs. When members consistently fill outside the preferred tier (whether due to habit, lack of communication, or limited access), the plan absorbs higher dispensing costs over time.
- Medication adherence. Members who fill 90-day supplies of maintenance medications tend to have higher adherence rates than those filling 30-day supplies. Adherence matters not just clinically but financially: poorly managed chronic conditions typically generate downstream medical costs through additional provider visits, ER use, or hospitalizations. Network designs that make 90-day fills convenient and cost-effective support better outcomes on both dimensions.
- Disruption risk. Network changes (pharmacies added or removed, tier reclassifications, new exclusivity arrangements) can significantly disrupt member routines.
The Specialty Pharmacy Layer
Specialty pharmacies warrant separate attention. These are pharmacies that dispense high-cost, complex medications (biologics, oncology drugs, treatments for rare conditions) that often require refrigeration, special handling, and patient education.
For plan sponsors, specialty spend is one of the highest-cost and fastest-growing components of pharmacy benefits. Specialty pharmacies are frequently subject to exclusive network arrangements in PBM contracts, meaning the plan may have limited flexibility in where these prescriptions are filled.
Understanding which specialty pharmacies are in-network, what reporting is available on specialty utilization, and whether exclusive arrangements are contractually mandated or discretionary is an important area of oversight.
What to Evaluate in Your Current Network
When reviewing a pharmacy benefits contract or preparing for a PBM procurement, the network structure deserves direct scrutiny. Key areas to assess:
- Preferred network composition. Which pharmacies are designated preferred, and does that match where your member population actually fills?
- 90-day supply access. Is the preferred 90-day network broad enough to be convenient, or does it funnel members to a single chain?
- Specialty pharmacy exclusivity. Are members required to use the PBM’s own specialty pharmacy? What visibility does the plan have into specialty dispensing?
- Network disruption analysis. If you are evaluating a PBM change, request a network disruption report that shows the number of impacted members and claims before any transition.
- Communication protocols. If a network change occurs mid-contract, what notification and member support does the PBM provide?
Managing Network Changes
Network changes are a normal part of pharmacy benefit management, but they carry real operational and member experience risk. When a pharmacy is removed from a preferred or standard network, members who relied on that location must change their behavior, and many won’t know until they show up at the counter.
Effective management of network changes involves advance member communication, clear guidance on alternative pharmacies, and support for members who need help transferring prescriptions. For plan sponsors, the key questions include:
- What does the PBM’s notification process look like?
- How much lead time will the plan receive?
- Is there continuity-of-care protection for members mid-treatment?
These questions are worth raising proactively in contract negotiations, not after a change has already taken effect.
