NADAC vs WAC vs AWP: Drug Pricing Explained
By Dylan Sanson, Pharmacist & Pharmacy Manager · Published
The pharmaceutical industry uses several pricing benchmarks, but they're not all created equal. Understanding the difference between NADAC and WAC is essential for any pharmacy professional managing drug costs.
The short answer
NADAC is built from actual pharmacy invoice data collected weekly by CMS, so it reflects what pharmacies really pay after discounts. WAC is the manufacturer's list price before discounts — a "sticker price" that typically runs higher, especially for generics. For reimbursement checks, purchasing decisions, and PBM negotiations, NADAC is the more accurate benchmark.
What Is WAC (Wholesale Acquisition Cost)?
WAC is the manufacturer's list price to wholesalers before any discounts, rebates, or other price concessions. Think of it as the "sticker price" — it rarely reflects what pharmacies actually pay.
What Is NADAC?
NADAC (National Average Drug Acquisition Cost) is based on actual pharmacy invoice data collected through weekly surveys by CMS. It captures what pharmacies really pay after all discounts and concessions — making it far more useful for cost analysis.
Key Differences at a Glance
| Feature | NADAC | WAC |
|---|---|---|
| Data source | Actual pharmacy invoices | Manufacturer list price |
| Discounts included | Yes | No |
| Update frequency | Weekly (Wednesdays) | Varies |
| Published by | CMS | Manufacturers |
| Accuracy for pharmacies | High | Low |
NADAC vs WAC: Which Reflects Real Pharmacy Cost?
NADAC reflects real pharmacy cost because CMS builds it from actual invoice data submitted by retail pharmacies. WAC is a manufacturer-published list price, so it sits above what most pharmacies pay once wholesaler discounts and contract terms are applied. If your question is "what did this drug actually cost my pharmacy?", NADAC is the closer answer.
Is WAC Higher Than NADAC?
For most generic drugs WAC is meaningfully higher than NADAC, since generics carry the deepest wholesaler discounts off list price. For brand drugs the two run closer together, because brand acquisition cost tends to track list price with smaller concessions. Compare both on a specific NDC rather than assuming a fixed spread.
Which Should Pharmacies Use?
For day-to-day cost analysis, reimbursement verification, and wholesaler negotiations, NADAC is the better benchmark. It reflects real market prices rather than artificial list prices. Use our free NADAC lookup tool to search current prices by drug name or NDC code, or run a claim through the reimbursement calculator.