NADAC (National Average Drug Acquisition Cost) is the weekly Medicaid benchmark of what U.S. retail pharmacies pay for drugs; the ASP pricing file is Medicare's quarterly payment limit for Part B drugs. Here is how to search both, what each number means, and how ClinicaLister shows them next to a drug's approvals, shortages and trials.
NADAC is a national average of the invoice prices that retail community pharmacies pay to acquire drugs. CMS builds it from a monthly survey of pharmacy invoice costs, conducted by a contractor, and publishes the rates every week as a per-unit price for each NDC (National Drug Code), with the pricing unit, an effective date, and whether the rate is set as a brand or a generic.
The ASP (Average Sales Price) pricing files are Medicare's quarterly payment limits for drugs billed under Part B — typically drugs administered in a clinic or hospital outpatient setting. Manufacturers report ASP each quarter, and CMS sets the payment limit for each HCPCS billing code, generally at ASP plus 6 percent. A separate NDC-HCPCS crosswalk maps package codes to billing codes.
Market access and health-economics teams use NADAC to compare pharmacy acquisition costs across a class and ASP to understand reimbursement for physician-administered products.
Both are free. NADAC lives on data.medicaid.gov; the ASP files on cms.gov.
On data.medicaid.gov, search for NADAC and open the dataset for the current year. Each year has its own dataset holding every weekly file for that calendar year.
Filter on the 11-digit NDC or on the NDC description. Read the price together with its pricing unit (each, mL or gram) and its effective date — the latest effective date is the current rate.
The companion "NADAC Comparison" dataset lists products whose rate was replaced this week, and "First Time NADAC Rates" lists products that received a rate for the first time.
On cms.gov, open the ASP pricing files page and download the Medicare Part B Drug Payment Limit File for the quarter you need, with the matching NDC-HCPCS crosswalk.
The payment limit file is keyed by HCPCS code. Use the crosswalk to connect a billing code to the NDCs (and so the products) it covers.
ClinicaLister keeps the latest NADAC rate for each NDC, refreshed weekly, and links it to the NDC Directory product — so the price shows up on the drug, not in a separate spreadsheet.
Quarterly ASP payment limits from 2021 onward are matched to products through the NDC-HCPCS crosswalk, so reimbursement trends are charted on the drug view.
Prices sit next to the drug's FDA approvals, shortages and Medicare Part D spending — the market-access picture in one place.
Through the ClinicaLister MCP server, Claude and other assistants can pull NADAC and ASP prices for a product in plain language alongside its trials and approvals.
32,600+
NDCs with a current NADAC rate
Weekly
NADAC refresh
16,000+
ASP payment-limit rows (HCPCS × quarter)
2021 →
ASP quarters held
ClinicaLister keeps the current NADAC rate per NDC, not the weekly history; use data.medicaid.gov for past rates. ASP is synced monthly and grows by one quarter at a time. Counts as of September 2026.
The National Average Drug Acquisition Cost: a weekly CMS benchmark of the average invoice price retail community pharmacies pay for a drug, per unit, by NDC. It comes from a monthly survey of pharmacy invoices.
Weekly. Each calendar year's rates are published as one dataset on data.medicaid.gov, with companion datasets for weekly rate changes and first-time rates.
NADAC measures what retail pharmacies pay to buy a drug and is used as a Medicaid benchmark. ASP is the manufacturer-reported average sales price that Medicare uses to set quarterly payment limits for Part B drugs, generally ASP plus 6 percent.
On cms.gov, under the Medicare Part B ASP pricing files. Each quarter has a payment limit file and an NDC-HCPCS crosswalk; files from before 2021 require accepting an AMA licence.
No. It keeps the current rate per NDC, refreshed weekly. For historical rates, use the yearly NADAC datasets on data.medicaid.gov.
See a drug's prices next to its approvals, shortages and trials
Built for the Market Access / HEOR. See it in the product: Drug & Device Details. All data sources