The Same Procedure Costs More Because of the Building It Happened In
Medicare pays substantially more for many services delivered in a hospital outpatient department than for the identical service in a physician office. The differential shaped two decades of hospital acquisition strategy.
One Service, Several Prices
An echocardiogram, an infusion, or a routine office visit can be delivered in a physician office, in a hospital outpatient department, or in an ambulatory surgical centre. The clinical service may be identical.
The payment is not. Medicare uses separate fee schedules for each setting, and rates in hospital outpatient departments have historically been substantially higher than in physician offices for the same service.
The gap is compounded by the facility fee, a separate charge for the use of the hospital facility, billed in addition to the professional fee for the physician work. A patient receiving the same care in a physician office receives one bill; in a hospital outpatient department they receive two.
The Original Justification
The differential was not arbitrary. Hospitals carry cost structures that independent offices do not.
They maintain emergency departments that must treat everyone regardless of ability to pay. They meet licensing, accreditation, and life safety requirements that do not apply to offices. They maintain standby capacity for complex cases and treat a payer mix weighted toward public programmes that reimburse below cost.
Paying hospitals more for outpatient services helped fund those obligations. That is a coherent policy, and it was designed for a world in which hospital outpatient departments were physically located in hospitals and served patients who might need that infrastructure.
| Setting | Payment Level | Separate Facility Fee |
|---|---|---|
| Physician office | Lower | No |
| Ambulatory surgical centre | Intermediate | Yes, at a lower rate |
| Hospital outpatient department | Higher | Yes |
A payment difference justified by infrastructure becomes something else entirely when the infrastructure does not change and only the ownership does. The building is the same building, the staff are the same staff, and the bill is different.
The Strategy It Created
The consequence was predictable and it happened at scale. A hospital system that acquires a physician practice can, subject to requirements, convert it into a hospital outpatient department and bill the same services at hospital rates.
Nothing about the location, the equipment, or the clinicians needs to change. The reimbursement does.
That arithmetic contributed materially to two decades of consolidation, with a large share of physicians moving from independent practice to hospital employment. Studies examining acquisitions have found meaningful price increases for the same services following ownership change, with the site of service differential identified as a significant driver.
The effect reaches patients directly, since cost sharing is calculated on the higher amount, and a patient can face a facility fee at a practice they have attended for years without any change they can observe.
The Policy Response
Legislation in 2015 addressed this partially through site neutral payment for newly acquired off campus outpatient departments, requiring that services at facilities that began billing after a cutoff date be paid at rates closer to the physician fee schedule.
The reform was significant and deliberately limited. Existing off campus departments were grandfathered, meaning facilities already converted continued to receive the higher rate. On campus departments were excluded entirely.
Subsequent regulatory attempts to extend site neutral payment to grandfathered facilities were challenged in court, with mixed outcomes turning on the scope of the agency authority rather than on the merits of the policy.
The Argument That Remains
The case for full site neutrality is straightforward: paying different amounts for identical services distorts where care is delivered, raises spending without improving outcomes, and subsidises consolidation.
The hospital case is that outpatient revenue cross subsidises services that lose money, that community hospitals in particular depend on it, and that removing the differential without replacing the funding would close service lines and, in some rural markets, whole facilities.
Both are true. The disagreement is about whether an untargeted payment differential is a sensible way to fund emergency and standby capacity, or whether that funding should be provided explicitly to the facilities that actually need it.
Analyses by the independent commission advising Congress on Medicare payment have consistently supported broader site neutrality, estimating substantial savings, while acknowledging the need for targeted support for hospitals serving vulnerable populations.
What It Means Commercially
For a hospital system, the share of outpatient revenue exposed to site neutral proposals is a material earnings sensitivity and is generally not quantified in disclosures. For physician practice management companies and independent operators, site neutrality is a competitive benefit, since it removes the acquisition premium a hospital can pay based on rebilling alone.
For anyone reading either sector, the grandfathering distinction matters. A system whose outpatient footprint is largely on campus or grandfathered is far less exposed than one that has been converting acquired practices recently.
The Bottom Line
Site of service payment differentials were designed to fund hospital infrastructure and became a reason to buy physician practices, because the same care in the same room bills differently once the sign changes. The partial reform in 2015 stopped the strategy prospectively and protected everything already converted, which is why the debate continues. The honest version of the argument is not about whether hospitals need cross subsidy, it is about whether paying more for identical care wherever a hospital happens to own the building is a defensible way to deliver it.