The 340B Drug Pricing Program is a federal program that requires drug manufacturers to sell outpatient medications at significantly reduced prices to hospitals and clinics that serve large numbers of low-income or uninsured patients. In 2024, covered entities purchased $81.4 billion in drugs through the program, representing about 16% of all U.S. prescription drug spending.
Created by Congress in 1992 as part of the Veterans Health Care Act, the program gets its name from Section 340B of the Public Health Service Act. The core idea is straightforward: safety-net providers that care for vulnerable populations shouldn’t pay full price for medications. By stretching their drug budgets, these organizations can reinvest savings into patient care, expanded services, or reduced costs for uninsured patients.
How the Pricing Works
Any drug manufacturer that wants its products covered by Medicaid must also agree to offer 340B pricing. This isn’t optional. If a manufacturer participates in the Medicaid Drug Rebate Program, it’s required to sign a 340B agreement with the federal government.
The discounted price, called the “ceiling price,” is calculated using a simple formula: the average manufacturer price minus a unit rebate amount. The average manufacturer price reflects what wholesalers typically pay for a drug, and the unit rebate amount is a discount already built into the Medicaid rebate system. Subtracting one from the other produces a price that can be 25% to 50% below what most buyers pay, sometimes more for generic drugs. Manufacturers cannot charge covered entities above this ceiling price.
The Health Resources and Services Administration, the federal agency that oversees 340B, publishes ceiling prices so participating entities know the maximum they should be paying for each drug.
Who Qualifies as a Covered Entity
Not every hospital or clinic can participate. HRSA maintains a list of specific provider types that are eligible, and each must register and meet ongoing requirements. The eligible categories fall into a few broad groups.
Federally qualified health centers make up a large portion of participants. These include community health centers that receive federal grants, look-alikes (which meet the same standards but don’t receive grant funding), Native Hawaiian health centers, and tribal and urban Indian health centers. Ryan White HIV/AIDS Program grantees, which provide care to people living with HIV, also qualify.
Several types of hospitals are eligible: children’s hospitals, critical access hospitals, free-standing cancer hospitals, rural referral centers, sole community hospitals, and disproportionate share hospitals. That last category covers hospitals where a high percentage of patients are on Medicaid or are uninsured, and it accounts for a significant share of 340B hospital purchases.
Specialized clinics round out the list, including family planning clinics, sexually transmitted disease clinics, tuberculosis clinics, hemophilia treatment centers, and black lung clinics.
Who Counts as a 340B Patient
Covered entities can only use 340B-priced drugs for their own patients. Federal guidelines from 1996 established a three-part test. An individual qualifies as a patient only if the entity maintains health care records for that person, the person receives care from a provider who is employed by or has an arrangement with the entity, and the services received are consistent with the type of care the entity is funded to provide. Disproportionate share hospitals are exempt from that third requirement.
This definition matters because one of the most common compliance violations involves “diversion,” where 340B drugs end up being dispensed to people who don’t meet the patient definition. Entities that can’t keep this boundary clean risk being removed from the program entirely.
Contract Pharmacies and Manufacturer Pushback
Many covered entities, especially smaller clinics, don’t operate their own pharmacies. Instead, they contract with outside retail pharmacies to dispense 340B drugs on their behalf. This contract pharmacy arrangement has expanded dramatically over the past two decades and has become one of the program’s biggest flashpoints.
At least 20 drug manufacturers have imposed restrictions on shipping 340B-priced drugs to contract pharmacies, arguing the original statute doesn’t require them to do so. HRSA pushed back in 2021, sending violation letters to manufacturers and threatening financial penalties. Several manufacturers then sued the agency, claiming it overstepped its authority. The legal battles are ongoing and have created real uncertainty for entities that depend on contract pharmacies to get discounted medications to their patients.
Avoiding Double Discounts on Medicaid
Federal law prohibits manufacturers from providing both a 340B discount and a Medicaid rebate on the same drug. Without safeguards, a manufacturer could end up paying a discount twice: once through the reduced 340B price and again through the rebate it owes to a state Medicaid program.
To prevent this, each covered entity must choose one of two approaches for its Medicaid fee-for-service patients. It can “carve in,” meaning it uses 340B drugs for Medicaid patients and ensures the state doesn’t also claim a rebate. Or it can “carve out,” purchasing drugs for Medicaid patients at regular prices so the standard rebate process stays intact. HRSA maintains a Medicaid Exclusion File that tracks each entity’s choice, and changes only take effect at the start of the following quarter.
Audits and Compliance
HRSA conducts audits of covered entities to check for two primary violations: diversion (dispensing 340B drugs to ineligible individuals) and duplicate discounts. When an audit finds noncompliance, the entity must develop a corrective action plan and complete it within six months. The entity is also responsible for contacting every affected manufacturer to arrange repayment for drugs that were improperly purchased at 340B prices.
Consequences escalate with repeated violations. A first finding typically results in a corrective plan and potential refunds to manufacturers. If a re-audit finds the same violation, HRSA may consider it systematic and intentional, which can lead to removal from the 340B program. Entities that are removed may also be barred from re-entering the program for a set period. HRSA posts public notices identifying entities with audit findings that require repayment, so manufacturers know to follow up.
The Dispute Resolution Process
When covered entities and manufacturers disagree over pricing, eligibility, or other 340B requirements, they can use an administrative dispute resolution process rather than going straight to court. A 2024 final rule overhauled how this process works, making several changes designed to benefit smaller providers.
The previous system, established in 2020, required disputes to meet a $25,000 minimum threshold before a claim could even be filed. The updated rule eliminated that floor, recognizing that many community-based clinics have legitimate disputes involving smaller amounts. The new process also replaced a panel drawn from multiple federal agencies with subject matter experts from HRSA’s Office of Pharmacy Affairs, who have direct knowledge of how the program operates. For the first time, either party can now seek reconsideration of a panel decision, an appeals option that didn’t exist under the old rules.
Why the Program Is Controversial
The 340B program has grown far beyond its original scope. Total purchases reached $81.4 billion in 2024, within a U.S. prescription drug market of roughly $495 billion. Drug manufacturers argue that the program has expanded to include large, financially healthy hospital systems that use 340B savings to boost revenue rather than directly benefit low-income patients. Critics point out that there’s no federal requirement for covered entities to pass their savings along to patients in the form of lower drug prices at the pharmacy counter.
Supporters counter that the program allows safety-net providers to fund services that would otherwise be financially impossible: free clinics, mental health programs, outreach to underserved communities, and sliding-scale prescription costs for uninsured patients. For a federally qualified health center operating on thin margins, the difference between 340B pricing and standard wholesale pricing can determine whether a program survives or shuts down.